mirror of
https://github.com/golang/go
synced 2024-11-21 21:24:45 -07:00
exp/datafmt: delete per Go 1 plan
R=r, bradfitz CC=golang-dev https://golang.org/cl/5249055
This commit is contained in:
Robert Griesemer
parent
e58a77809d
commit
187c3536a8
@ -76,7 +76,6 @@ DIRS=\
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encoding/hex\
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encoding/pem\
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exec\
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exp/datafmt\
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exp/ebnf\
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exp/ebnflint\
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exp/gui\
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@ -1,12 +0,0 @@
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# Copyright 2009 The Go Authors. All rights reserved.
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# Use of this source code is governed by a BSD-style
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# license that can be found in the LICENSE file.
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include ../../../Make.inc
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TARG=exp/datafmt
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GOFILES=\
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datafmt.go\
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parser.go\
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include ../../../Make.pkg
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@ -1,710 +0,0 @@
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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/* Package datafmt implements syntax-directed, type-driven formatting
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of arbitrary data structures. Formatting a data structure consists of
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two phases: first, a parser reads a format specification and builds a
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"compiled" format. Then, the format can be applied repeatedly to
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arbitrary values. Applying a format to a value evaluates to a []byte
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containing the formatted value bytes, or nil.
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A format specification is a set of package declarations and format rules:
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Format = [ Entry { ";" Entry } [ ";" ] ] .
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Entry = PackageDecl | FormatRule .
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(The syntax of a format specification is presented in the same EBNF
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notation as used in the Go language specification. The syntax of white
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space, comments, identifiers, and string literals is the same as in Go.)
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A package declaration binds a package name (such as 'ast') to a
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package import path (such as '"go/ast"'). Each package used (in
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a type name, see below) must be declared once before use.
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PackageDecl = PackageName ImportPath .
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PackageName = identifier .
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ImportPath = string .
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A format rule binds a rule name to a format expression. A rule name
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may be a type name or one of the special names 'default' or '/'.
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A type name may be the name of a predeclared type (for example, 'int',
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'float32', etc.), the package-qualified name of a user-defined type
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(for example, 'ast.MapType'), or an identifier indicating the structure
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of unnamed composite types ('array', 'chan', 'func', 'interface', 'map',
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or 'ptr'). Each rule must have a unique name; rules can be declared in
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any order.
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FormatRule = RuleName "=" Expression .
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RuleName = TypeName | "default" | "/" .
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TypeName = [ PackageName "." ] identifier .
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To format a value, the value's type name is used to select the format rule
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(there is an override mechanism, see below). The format expression of the
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selected rule specifies how the value is formatted. Each format expression,
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when applied to a value, evaluates to a byte sequence or nil.
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In its most general form, a format expression is a list of alternatives,
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each of which is a sequence of operands:
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Expression = [ Sequence ] { "|" [ Sequence ] } .
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Sequence = Operand { Operand } .
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The formatted result produced by an expression is the result of the first
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alternative sequence that evaluates to a non-nil result; if there is no
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such alternative, the expression evaluates to nil. The result produced by
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an operand sequence is the concatenation of the results of its operands.
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If any operand in the sequence evaluates to nil, the entire sequence
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evaluates to nil.
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There are five kinds of operands:
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Operand = Literal | Field | Group | Option | Repetition .
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Literals evaluate to themselves, with two substitutions. First,
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%-formats expand in the manner of fmt.Printf, with the current value
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passed as the parameter. Second, the current indentation (see below)
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is inserted after every newline or form feed character.
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Literal = string .
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This table shows string literals applied to the value 42 and the
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corresponding formatted result:
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"foo" foo
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"%x" 2a
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"x = %d" x = 42
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"%#x = %d" 0x2a = 42
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A field operand is a field name optionally followed by an alternate
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rule name. The field name may be an identifier or one of the special
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names @ or *.
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Field = FieldName [ ":" RuleName ] .
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FieldName = identifier | "@" | "*" .
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If the field name is an identifier, the current value must be a struct,
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and there must be a field with that name in the struct. The same lookup
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rules apply as in the Go language (for instance, the name of an anonymous
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field is the unqualified type name). The field name denotes the field
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value in the struct. If the field is not found, formatting is aborted
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and an error message is returned. (TODO consider changing the semantics
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such that if a field is not found, it evaluates to nil).
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The special name '@' denotes the current value.
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The meaning of the special name '*' depends on the type of the current
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value:
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array, slice types array, slice element (inside {} only, see below)
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interfaces value stored in interface
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pointers value pointed to by pointer
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(Implementation restriction: channel, function and map types are not
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supported due to missing reflection support).
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Fields are evaluated as follows: If the field value is nil, or an array
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or slice element does not exist, the result is nil (see below for details
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on array/slice elements). If the value is not nil the field value is
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formatted (recursively) using the rule corresponding to its type name,
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or the alternate rule name, if given.
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The following example shows a complete format specification for a
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struct 'myPackage.Point'. Assume the package
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package myPackage // in directory myDir/myPackage
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type Point struct {
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name string;
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x, y int;
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}
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Applying the format specification
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myPackage "myDir/myPackage";
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int = "%d";
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hexInt = "0x%x";
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string = "---%s---";
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myPackage.Point = name "{" x ", " y:hexInt "}";
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to the value myPackage.Point{"foo", 3, 15} results in
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---foo---{3, 0xf}
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Finally, an operand may be a grouped, optional, or repeated expression.
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A grouped expression ("group") groups a more complex expression (body)
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so that it can be used in place of a single operand:
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Group = "(" [ Indentation ">>" ] Body ")" .
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Indentation = Expression .
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Body = Expression .
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A group body may be prefixed by an indentation expression followed by '>>'.
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The indentation expression is applied to the current value like any other
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expression and the result, if not nil, is appended to the current indentation
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during the evaluation of the body (see also formatting state, below).
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An optional expression ("option") is enclosed in '[]' brackets.
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Option = "[" Body "]" .
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An option evaluates to its body, except that if the body evaluates to nil,
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the option expression evaluates to an empty []byte. Thus an option's purpose
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is to protect the expression containing the option from a nil operand.
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A repeated expression ("repetition") is enclosed in '{}' braces.
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Repetition = "{" Body [ "/" Separator ] "}" .
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Separator = Expression .
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A repeated expression is evaluated as follows: The body is evaluated
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repeatedly and its results are concatenated until the body evaluates
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to nil. The result of the repetition is the (possibly empty) concatenation,
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but it is never nil. An implicit index is supplied for the evaluation of
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the body: that index is used to address elements of arrays or slices. If
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the corresponding elements do not exist, the field denoting the element
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evaluates to nil (which in turn may terminate the repetition).
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The body of a repetition may be followed by a '/' and a "separator"
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expression. If the separator is present, it is invoked between repetitions
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of the body.
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The following example shows a complete format specification for formatting
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a slice of unnamed type. Applying the specification
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int = "%b";
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array = { * / ", " }; // array is the type name for an unnamed slice
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to the value '[]int{2, 3, 5, 7}' results in
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10, 11, 101, 111
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Default rule: If a format rule named 'default' is present, it is used for
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formatting a value if no other rule was found. A common default rule is
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default = "%v"
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to provide default formatting for basic types without having to specify
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a specific rule for each basic type.
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Global separator rule: If a format rule named '/' is present, it is
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invoked with the current value between literals. If the separator
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expression evaluates to nil, it is ignored.
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For instance, a global separator rule may be used to punctuate a sequence
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of values with commas. The rules:
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default = "%v";
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/ = ", ";
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will format an argument list by printing each one in its default format,
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separated by a comma and a space.
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*/
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package datafmt
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import (
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"bytes"
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"fmt"
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"go/token"
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"io"
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"os"
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"reflect"
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"runtime"
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)
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// ----------------------------------------------------------------------------
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// Format representation
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// Custom formatters implement the Formatter function type.
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// A formatter is invoked with the current formatting state, the
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// value to format, and the rule name under which the formatter
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// was installed (the same formatter function may be installed
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// under different names). The formatter may access the current state
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// to guide formatting and use State.Write to append to the state's
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// output.
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//
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// A formatter must return a boolean value indicating if it evaluated
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// to a non-nil value (true), or a nil value (false).
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//
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type Formatter func(state *State, value interface{}, ruleName string) bool
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// A FormatterMap is a set of custom formatters.
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// It maps a rule name to a formatter function.
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//
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type FormatterMap map[string]Formatter
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// A parsed format expression is built from the following nodes.
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//
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type (
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expr interface{}
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alternatives []expr // x | y | z
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sequence []expr // x y z
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literal [][]byte // a list of string segments, possibly starting with '%'
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field struct {
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fieldName string // including "@", "*"
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ruleName string // "" if no rule name specified
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}
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group struct {
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indent, body expr // (indent >> body)
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}
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option struct {
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body expr // [body]
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}
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repetition struct {
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body, separator expr // {body / separator}
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}
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custom struct {
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ruleName string
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fun Formatter
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}
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)
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// A Format is the result of parsing a format specification.
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// The format may be applied repeatedly to format values.
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//
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type Format map[string]expr
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// ----------------------------------------------------------------------------
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// Formatting
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// An application-specific environment may be provided to Format.Apply;
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// the environment is available inside custom formatters via State.Env().
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// Environments must implement copying; the Copy method must return an
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// complete copy of the receiver. This is necessary so that the formatter
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// can save and restore an environment (in case of an absent expression).
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//
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// If the Environment doesn't change during formatting (this is under
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// control of the custom formatters), the Copy function can simply return
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// the receiver, and thus can be very light-weight.
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//
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type Environment interface {
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Copy() Environment
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}
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// State represents the current formatting state.
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// It is provided as argument to custom formatters.
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//
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type State struct {
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fmt Format // format in use
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env Environment // user-supplied environment
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errors chan os.Error // not chan *Error (errors <- nil would be wrong!)
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hasOutput bool // true after the first literal has been written
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indent bytes.Buffer // current indentation
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output bytes.Buffer // format output
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linePos token.Position // position of line beginning (Column == 0)
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default_ expr // possibly nil
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separator expr // possibly nil
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}
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func newState(fmt Format, env Environment, errors chan os.Error) *State {
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s := new(State)
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s.fmt = fmt
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s.env = env
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s.errors = errors
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s.linePos = token.Position{Line: 1}
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// if we have a default rule, cache its expression for fast access
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if x, found := fmt["default"]; found {
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s.default_ = x
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}
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// if we have a global separator rule, cache its expression for fast access
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if x, found := fmt["/"]; found {
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s.separator = x
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}
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|
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return s
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}
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// Env returns the environment passed to Format.Apply.
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func (s *State) Env() interface{} { return s.env }
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|
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// LinePos returns the position of the current line beginning
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// in the state's output buffer. Line numbers start at 1.
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//
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func (s *State) LinePos() token.Position { return s.linePos }
|
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|
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// Pos returns the position of the next byte to be written to the
|
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// output buffer. Line numbers start at 1.
|
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//
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func (s *State) Pos() token.Position {
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offs := s.output.Len()
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return token.Position{Line: s.linePos.Line, Column: offs - s.linePos.Offset, Offset: offs}
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}
|
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|
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// Write writes data to the output buffer, inserting the indentation
|
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// string after each newline or form feed character. It cannot return an error.
|
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//
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func (s *State) Write(data []byte) (int, os.Error) {
|
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n := 0
|
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i0 := 0
|
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for i, ch := range data {
|
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if ch == '\n' || ch == '\f' {
|
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// write text segment and indentation
|
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n1, _ := s.output.Write(data[i0 : i+1])
|
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n2, _ := s.output.Write(s.indent.Bytes())
|
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n += n1 + n2
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i0 = i + 1
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s.linePos.Offset = s.output.Len()
|
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s.linePos.Line++
|
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}
|
||||
}
|
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n3, _ := s.output.Write(data[i0:])
|
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return n + n3, nil
|
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}
|
||||
|
||||
type checkpoint struct {
|
||||
env Environment
|
||||
hasOutput bool
|
||||
outputLen int
|
||||
linePos token.Position
|
||||
}
|
||||
|
||||
func (s *State) save() checkpoint {
|
||||
saved := checkpoint{nil, s.hasOutput, s.output.Len(), s.linePos}
|
||||
if s.env != nil {
|
||||
saved.env = s.env.Copy()
|
||||
}
|
||||
return saved
|
||||
}
|
||||
|
||||
func (s *State) restore(m checkpoint) {
|
||||
s.env = m.env
|
||||
s.output.Truncate(m.outputLen)
|
||||
}
|
||||
|
||||
func (s *State) error(msg string) {
|
||||
s.errors <- os.NewError(msg)
|
||||
runtime.Goexit()
|
||||
}
|
||||
|
||||
// TODO At the moment, unnamed types are simply mapped to the default
|
||||
// names below. For instance, all unnamed arrays are mapped to
|
||||
// 'array' which is not really sufficient. Eventually one may want
|
||||
// to be able to specify rules for say an unnamed slice of T.
|
||||
//
|
||||
|
||||
func typename(typ reflect.Type) string {
|
||||
switch typ.Kind() {
|
||||
case reflect.Array:
|
||||
return "array"
|
||||
case reflect.Slice:
|
||||
return "array"
|
||||
case reflect.Chan:
|
||||
return "chan"
|
||||
case reflect.Func:
|
||||
return "func"
|
||||
case reflect.Interface:
|
||||
return "interface"
|
||||
case reflect.Map:
|
||||
return "map"
|
||||
case reflect.Ptr:
|
||||
return "ptr"
|
||||
}
|
||||
return typ.String()
|
||||
}
|
||||
|
||||
func (s *State) getFormat(name string) expr {
|
||||
if fexpr, found := s.fmt[name]; found {
|
||||
return fexpr
|
||||
}
|
||||
|
||||
if s.default_ != nil {
|
||||
return s.default_
|
||||
}
|
||||
|
||||
s.error(fmt.Sprintf("no format rule for type: '%s'", name))
|
||||
return nil
|
||||
}
|
||||
|
||||
// eval applies a format expression fexpr to a value. If the expression
|
||||
// evaluates internally to a non-nil []byte, that slice is appended to
|
||||
// the state's output buffer and eval returns true. Otherwise, eval
|
||||
// returns false and the state remains unchanged.
|
||||
//
|
||||
func (s *State) eval(fexpr expr, value reflect.Value, index int) bool {
|
||||
// an empty format expression always evaluates
|
||||
// to a non-nil (but empty) []byte
|
||||
if fexpr == nil {
|
||||
return true
|
||||
}
|
||||
|
||||
switch t := fexpr.(type) {
|
||||
case alternatives:
|
||||
// append the result of the first alternative that evaluates to
|
||||
// a non-nil []byte to the state's output
|
||||
mark := s.save()
|
||||
for _, x := range t {
|
||||
if s.eval(x, value, index) {
|
||||
return true
|
||||
}
|
||||
s.restore(mark)
|
||||
}
|
||||
return false
|
||||
|
||||
case sequence:
|
||||
// append the result of all operands to the state's output
|
||||
// unless a nil result is encountered
|
||||
mark := s.save()
|
||||
for _, x := range t {
|
||||
if !s.eval(x, value, index) {
|
||||
s.restore(mark)
|
||||
return false
|
||||
}
|
||||
}
|
||||
return true
|
||||
|
||||
case literal:
|
||||
// write separator, if any
|
||||
if s.hasOutput {
|
||||
// not the first literal
|
||||
if s.separator != nil {
|
||||
sep := s.separator // save current separator
|
||||
s.separator = nil // and disable it (avoid recursion)
|
||||
mark := s.save()
|
||||
if !s.eval(sep, value, index) {
|
||||
s.restore(mark)
|
||||
}
|
||||
s.separator = sep // enable it again
|
||||
}
|
||||
}
|
||||
s.hasOutput = true
|
||||
// write literal segments
|
||||
for _, lit := range t {
|
||||
if len(lit) > 1 && lit[0] == '%' {
|
||||
// segment contains a %-format at the beginning
|
||||
if lit[1] == '%' {
|
||||
// "%%" is printed as a single "%"
|
||||
s.Write(lit[1:])
|
||||
} else {
|
||||
// use s instead of s.output to get indentation right
|
||||
fmt.Fprintf(s, string(lit), value.Interface())
|
||||
}
|
||||
} else {
|
||||
// segment contains no %-formats
|
||||
s.Write(lit)
|
||||
}
|
||||
}
|
||||
return true // a literal never evaluates to nil
|
||||
|
||||
case *field:
|
||||
// determine field value
|
||||
switch t.fieldName {
|
||||
case "@":
|
||||
// field value is current value
|
||||
|
||||
case "*":
|
||||
// indirection: operation is type-specific
|
||||
switch v := value; v.Kind() {
|
||||
case reflect.Array:
|
||||
if v.Len() <= index {
|
||||
return false
|
||||
}
|
||||
value = v.Index(index)
|
||||
|
||||
case reflect.Slice:
|
||||
if v.IsNil() || v.Len() <= index {
|
||||
return false
|
||||
}
|
||||
value = v.Index(index)
|
||||
|
||||
case reflect.Map:
|
||||
s.error("reflection support for maps incomplete")
|
||||
|
||||
case reflect.Ptr:
|
||||
if v.IsNil() {
|
||||
return false
|
||||
}
|
||||
value = v.Elem()
|
||||
|
||||
case reflect.Interface:
|
||||
if v.IsNil() {
|
||||
return false
|
||||
}
|
||||
value = v.Elem()
|
||||
|
||||
case reflect.Chan:
|
||||
s.error("reflection support for chans incomplete")
|
||||
|
||||
case reflect.Func:
|
||||
s.error("reflection support for funcs incomplete")
|
||||
|
||||
default:
|
||||
s.error(fmt.Sprintf("error: * does not apply to `%s`", value.Type()))
|
||||
}
|
||||
|
||||
default:
|
||||
// value is value of named field
|
||||
var field reflect.Value
|
||||
if sval := value; sval.Kind() == reflect.Struct {
|
||||
field = sval.FieldByName(t.fieldName)
|
||||
if !field.IsValid() {
|
||||
// TODO consider just returning false in this case
|
||||
s.error(fmt.Sprintf("error: no field `%s` in `%s`", t.fieldName, value.Type()))
|
||||
}
|
||||
}
|
||||
value = field
|
||||
}
|
||||
|
||||
// determine rule
|
||||
ruleName := t.ruleName
|
||||
if ruleName == "" {
|
||||
// no alternate rule name, value type determines rule
|
||||
ruleName = typename(value.Type())
|
||||
}
|
||||
fexpr = s.getFormat(ruleName)
|
||||
|
||||
mark := s.save()
|
||||
if !s.eval(fexpr, value, index) {
|
||||
s.restore(mark)
|
||||
return false
|
||||
}
|
||||
return true
|
||||
|
||||
case *group:
|
||||
// remember current indentation
|
||||
indentLen := s.indent.Len()
|
||||
|
||||
// update current indentation
|
||||
mark := s.save()
|
||||
s.eval(t.indent, value, index)
|
||||
// if the indentation evaluates to nil, the state's output buffer
|
||||
// didn't change - either way it's ok to append the difference to
|
||||
// the current indentation
|
||||
s.indent.Write(s.output.Bytes()[mark.outputLen:s.output.Len()])
|
||||
s.restore(mark)
|
||||
|
||||
// format group body
|
||||
mark = s.save()
|
||||
b := true
|
||||
if !s.eval(t.body, value, index) {
|
||||
s.restore(mark)
|
||||
b = false
|
||||
}
|
||||
|
||||
// reset indentation
|
||||
s.indent.Truncate(indentLen)
|
||||
return b
|
||||
|
||||
case *option:
|
||||
// evaluate the body and append the result to the state's output
|
||||
// buffer unless the result is nil
|
||||
mark := s.save()
|
||||
if !s.eval(t.body, value, 0) { // TODO is 0 index correct?
|
||||
s.restore(mark)
|
||||
}
|
||||
return true // an option never evaluates to nil
|
||||
|
||||
case *repetition:
|
||||
// evaluate the body and append the result to the state's output
|
||||
// buffer until a result is nil
|
||||
for i := 0; ; i++ {
|
||||
mark := s.save()
|
||||
// write separator, if any
|
||||
if i > 0 && t.separator != nil {
|
||||
// nil result from separator is ignored
|
||||
mark := s.save()
|
||||
if !s.eval(t.separator, value, i) {
|
||||
s.restore(mark)
|
||||
}
|
||||
}
|
||||
if !s.eval(t.body, value, i) {
|
||||
s.restore(mark)
|
||||
break
|
||||
}
|
||||
}
|
||||
return true // a repetition never evaluates to nil
|
||||
|
||||
case *custom:
|
||||
// invoke the custom formatter to obtain the result
|
||||
mark := s.save()
|
||||
if !t.fun(s, value.Interface(), t.ruleName) {
|
||||
s.restore(mark)
|
||||
return false
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
panic("unreachable")
|
||||
return false
|
||||
}
|
||||
|
||||
// Eval formats each argument according to the format
|
||||
// f and returns the resulting []byte and os.Error. If
|
||||
// an error occurred, the []byte contains the partially
|
||||
// formatted result. An environment env may be passed
|
||||
// in which is available in custom formatters through
|
||||
// the state parameter.
|
||||
//
|
||||
func (f Format) Eval(env Environment, args ...interface{}) ([]byte, os.Error) {
|
||||
if f == nil {
|
||||
return nil, os.NewError("format is nil")
|
||||
}
|
||||
|
||||
errors := make(chan os.Error)
|
||||
s := newState(f, env, errors)
|
||||
|
||||
go func() {
|
||||
for _, v := range args {
|
||||
fld := reflect.ValueOf(v)
|
||||
if !fld.IsValid() {
|
||||
errors <- os.NewError("nil argument")
|
||||
return
|
||||
}
|
||||
mark := s.save()
|
||||
if !s.eval(s.getFormat(typename(fld.Type())), fld, 0) { // TODO is 0 index correct?
|
||||
s.restore(mark)
|
||||
}
|
||||
}
|
||||
errors <- nil // no errors
|
||||
}()
|
||||
|
||||
err := <-errors
|
||||
return s.output.Bytes(), err
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Convenience functions
|
||||
|
||||
// Fprint formats each argument according to the format f
|
||||
// and writes to w. The result is the total number of bytes
|
||||
// written and an os.Error, if any.
|
||||
//
|
||||
func (f Format) Fprint(w io.Writer, env Environment, args ...interface{}) (int, os.Error) {
|
||||
data, err := f.Eval(env, args...)
|
||||
if err != nil {
|
||||
// TODO should we print partial result in case of error?
|
||||
return 0, err
|
||||
}
|
||||
return w.Write(data)
|
||||
}
|
||||
|
||||
// Print formats each argument according to the format f
|
||||
// and writes to standard output. The result is the total
|
||||
// number of bytes written and an os.Error, if any.
|
||||
//
|
||||
func (f Format) Print(args ...interface{}) (int, os.Error) {
|
||||
return f.Fprint(os.Stdout, nil, args...)
|
||||
}
|
||||
|
||||
// Sprint formats each argument according to the format f
|
||||
// and returns the resulting string. If an error occurs
|
||||
// during formatting, the result string contains the
|
||||
// partially formatted result followed by an error message.
|
||||
//
|
||||
func (f Format) Sprint(args ...interface{}) string {
|
||||
var buf bytes.Buffer
|
||||
_, err := f.Fprint(&buf, nil, args...)
|
||||
if err != nil {
|
||||
var i interface{} = args
|
||||
fmt.Fprintf(&buf, "--- Sprint(%s) failed: %v", fmt.Sprint(i), err)
|
||||
}
|
||||
return buf.String()
|
||||
}
|
||||
@ -1,330 +0,0 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package datafmt
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"testing"
|
||||
"go/token"
|
||||
)
|
||||
|
||||
var fset = token.NewFileSet()
|
||||
|
||||
func parse(t *testing.T, form string, fmap FormatterMap) Format {
|
||||
f, err := Parse(fset, "", []byte(form), fmap)
|
||||
if err != nil {
|
||||
t.Errorf("Parse(%s): %v", form, err)
|
||||
return nil
|
||||
}
|
||||
return f
|
||||
}
|
||||
|
||||
func verify(t *testing.T, f Format, expected string, args ...interface{}) {
|
||||
if f == nil {
|
||||
return // allow other tests to run
|
||||
}
|
||||
result := f.Sprint(args...)
|
||||
if result != expected {
|
||||
t.Errorf(
|
||||
"result : `%s`\nexpected: `%s`\n\n",
|
||||
result, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func formatter(s *State, value interface{}, rule_name string) bool {
|
||||
switch rule_name {
|
||||
case "/":
|
||||
fmt.Fprintf(s, "%d %d %d", s.Pos().Line, s.LinePos().Column, s.Pos().Column)
|
||||
return true
|
||||
case "blank":
|
||||
s.Write([]byte{' '})
|
||||
return true
|
||||
case "int":
|
||||
if value.(int)&1 == 0 {
|
||||
fmt.Fprint(s, "even ")
|
||||
} else {
|
||||
fmt.Fprint(s, "odd ")
|
||||
}
|
||||
return true
|
||||
case "nil":
|
||||
return false
|
||||
case "testing.T":
|
||||
s.Write([]byte("testing.T"))
|
||||
return true
|
||||
}
|
||||
panic("unreachable")
|
||||
return false
|
||||
}
|
||||
|
||||
func TestCustomFormatters(t *testing.T) {
|
||||
fmap0 := FormatterMap{"/": formatter}
|
||||
fmap1 := FormatterMap{"int": formatter, "blank": formatter, "nil": formatter}
|
||||
fmap2 := FormatterMap{"testing.T": formatter}
|
||||
|
||||
f := parse(t, `int=`, fmap0)
|
||||
verify(t, f, ``, 1, 2, 3)
|
||||
|
||||
f = parse(t, `int="#"`, nil)
|
||||
verify(t, f, `###`, 1, 2, 3)
|
||||
|
||||
f = parse(t, `int="#";string="%s"`, fmap0)
|
||||
verify(t, f, "#1 0 1#1 0 7#1 0 13\n2 0 0foo2 0 8\n", 1, 2, 3, "\n", "foo", "\n")
|
||||
|
||||
f = parse(t, ``, fmap1)
|
||||
verify(t, f, `even odd even odd `, 0, 1, 2, 3)
|
||||
|
||||
f = parse(t, `/ =@:blank; float64="#"`, fmap1)
|
||||
verify(t, f, `# # #`, 0.0, 1.0, 2.0)
|
||||
|
||||
f = parse(t, `float64=@:nil`, fmap1)
|
||||
verify(t, f, ``, 0.0, 1.0, 2.0)
|
||||
|
||||
f = parse(t, `testing "testing"; ptr=*`, fmap2)
|
||||
verify(t, f, `testing.T`, t)
|
||||
|
||||
// TODO needs more tests
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting of basic and simple composite types
|
||||
|
||||
func check(t *testing.T, form, expected string, args ...interface{}) {
|
||||
f := parse(t, form, nil)
|
||||
if f == nil {
|
||||
return // allow other tests to run
|
||||
}
|
||||
result := f.Sprint(args...)
|
||||
if result != expected {
|
||||
t.Errorf(
|
||||
"format : %s\nresult : `%s`\nexpected: `%s`\n\n",
|
||||
form, result, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestBasicTypes(t *testing.T) {
|
||||
check(t, ``, ``)
|
||||
check(t, `bool=":%v"`, `:true:false`, true, false)
|
||||
check(t, `int="%b %d %o 0x%x"`, `101010 42 52 0x2a`, 42)
|
||||
|
||||
check(t, `int="%"`, `%`, 42)
|
||||
check(t, `int="%%"`, `%`, 42)
|
||||
check(t, `int="**%%**"`, `**%**`, 42)
|
||||
check(t, `int="%%%%%%"`, `%%%`, 42)
|
||||
check(t, `int="%%%d%%"`, `%42%`, 42)
|
||||
|
||||
const i = -42
|
||||
const is = `-42`
|
||||
check(t, `int ="%d"`, is, i)
|
||||
check(t, `int8 ="%d"`, is, int8(i))
|
||||
check(t, `int16="%d"`, is, int16(i))
|
||||
check(t, `int32="%d"`, is, int32(i))
|
||||
check(t, `int64="%d"`, is, int64(i))
|
||||
|
||||
const u = 42
|
||||
const us = `42`
|
||||
check(t, `uint ="%d"`, us, uint(u))
|
||||
check(t, `uint8 ="%d"`, us, uint8(u))
|
||||
check(t, `uint16="%d"`, us, uint16(u))
|
||||
check(t, `uint32="%d"`, us, uint32(u))
|
||||
check(t, `uint64="%d"`, us, uint64(u))
|
||||
|
||||
const f = 3.141592
|
||||
const fs = `3.141592`
|
||||
check(t, `float64="%g"`, fs, f)
|
||||
check(t, `float32="%g"`, fs, float32(f))
|
||||
check(t, `float64="%g"`, fs, float64(f))
|
||||
}
|
||||
|
||||
func TestArrayTypes(t *testing.T) {
|
||||
var a0 [10]int
|
||||
check(t, `array="array";`, `array`, a0)
|
||||
|
||||
a1 := [...]int{1, 2, 3}
|
||||
check(t, `array="array";`, `array`, a1)
|
||||
check(t, `array={*}; int="%d";`, `123`, a1)
|
||||
check(t, `array={* / ", "}; int="%d";`, `1, 2, 3`, a1)
|
||||
check(t, `array={* / *}; int="%d";`, `12233`, a1)
|
||||
|
||||
a2 := []interface{}{42, "foo", 3.14}
|
||||
check(t, `array={* / ", "}; interface=*; string="bar"; default="%v";`, `42, bar, 3.14`, a2)
|
||||
}
|
||||
|
||||
func TestChanTypes(t *testing.T) {
|
||||
var c0 chan int
|
||||
check(t, `chan="chan"`, `chan`, c0)
|
||||
|
||||
c1 := make(chan int)
|
||||
go func() { c1 <- 42 }()
|
||||
check(t, `chan="chan"`, `chan`, c1)
|
||||
// check(t, `chan=*`, `42`, c1); // reflection support for chans incomplete
|
||||
}
|
||||
|
||||
func TestFuncTypes(t *testing.T) {
|
||||
var f0 func() int
|
||||
check(t, `func="func"`, `func`, f0)
|
||||
|
||||
f1 := func() int { return 42 }
|
||||
check(t, `func="func"`, `func`, f1)
|
||||
// check(t, `func=*`, `42`, f1); // reflection support for funcs incomplete
|
||||
}
|
||||
|
||||
func TestMapTypes(t *testing.T) {
|
||||
var m0 map[string]int
|
||||
check(t, `map="map"`, `map`, m0)
|
||||
|
||||
m1 := map[string]int{}
|
||||
check(t, `map="map"`, `map`, m1)
|
||||
// check(t, `map=*`, ``, m1); // reflection support for maps incomplete
|
||||
}
|
||||
|
||||
func TestPointerTypes(t *testing.T) {
|
||||
var p0 *int
|
||||
check(t, `ptr="ptr"`, `ptr`, p0)
|
||||
check(t, `ptr=*`, ``, p0)
|
||||
check(t, `ptr=*|"nil"`, `nil`, p0)
|
||||
|
||||
x := 99991
|
||||
p1 := &x
|
||||
check(t, `ptr="ptr"`, `ptr`, p1)
|
||||
check(t, `ptr=*; int="%d"`, `99991`, p1)
|
||||
}
|
||||
|
||||
func TestDefaultRule(t *testing.T) {
|
||||
check(t, `default="%v"`, `42foo3.14`, 42, "foo", 3.14)
|
||||
check(t, `default="%v"; int="%x"`, `abcdef`, 10, 11, 12, 13, 14, 15)
|
||||
check(t, `default="%v"; int="%x"`, `ab**ef`, 10, 11, "**", 14, 15)
|
||||
check(t, `default="%x"; int=@:default`, `abcdef`, 10, 11, 12, 13, 14, 15)
|
||||
}
|
||||
|
||||
func TestGlobalSeparatorRule(t *testing.T) {
|
||||
check(t, `int="%d"; / ="-"`, `1-2-3-4`, 1, 2, 3, 4)
|
||||
check(t, `int="%x%x"; / ="*"`, `aa*aa`, 10, 10)
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting of a struct
|
||||
|
||||
type T1 struct {
|
||||
a int
|
||||
}
|
||||
|
||||
const F1 = `datafmt "datafmt";` +
|
||||
`int = "%d";` +
|
||||
`datafmt.T1 = "<" a ">";`
|
||||
|
||||
func TestStruct1(t *testing.T) { check(t, F1, "<42>", T1{42}) }
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting of a struct with an optional field (ptr)
|
||||
|
||||
type T2 struct {
|
||||
s string
|
||||
p *T1
|
||||
}
|
||||
|
||||
const F2a = F1 +
|
||||
`string = "%s";` +
|
||||
`ptr = *;` +
|
||||
`datafmt.T2 = s ["-" p "-"];`
|
||||
|
||||
const F2b = F1 +
|
||||
`string = "%s";` +
|
||||
`ptr = *;` +
|
||||
`datafmt.T2 = s ("-" p "-" | "empty");`
|
||||
|
||||
func TestStruct2(t *testing.T) {
|
||||
check(t, F2a, "foo", T2{"foo", nil})
|
||||
check(t, F2a, "bar-<17>-", T2{"bar", &T1{17}})
|
||||
check(t, F2b, "fooempty", T2{"foo", nil})
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting of a struct with a repetitive field (slice)
|
||||
|
||||
type T3 struct {
|
||||
s string
|
||||
a []int
|
||||
}
|
||||
|
||||
const F3a = `datafmt "datafmt";` +
|
||||
`default = "%v";` +
|
||||
`array = *;` +
|
||||
`datafmt.T3 = s {" " a a / ","};`
|
||||
|
||||
const F3b = `datafmt "datafmt";` +
|
||||
`int = "%d";` +
|
||||
`string = "%s";` +
|
||||
`array = *;` +
|
||||
`nil = ;` +
|
||||
`empty = *:nil;` +
|
||||
`datafmt.T3 = s [a:empty ": " {a / "-"}]`
|
||||
|
||||
func TestStruct3(t *testing.T) {
|
||||
check(t, F3a, "foo", T3{"foo", nil})
|
||||
check(t, F3a, "foo 00, 11, 22", T3{"foo", []int{0, 1, 2}})
|
||||
check(t, F3b, "bar", T3{"bar", nil})
|
||||
check(t, F3b, "bal: 2-3-5", T3{"bal", []int{2, 3, 5}})
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting of a struct with alternative field
|
||||
|
||||
type T4 struct {
|
||||
x *int
|
||||
a []int
|
||||
}
|
||||
|
||||
const F4a = `datafmt "datafmt";` +
|
||||
`int = "%d";` +
|
||||
`ptr = *;` +
|
||||
`array = *;` +
|
||||
`nil = ;` +
|
||||
`empty = *:nil;` +
|
||||
`datafmt.T4 = "<" (x:empty x | "-") ">" `
|
||||
|
||||
const F4b = `datafmt "datafmt";` +
|
||||
`int = "%d";` +
|
||||
`ptr = *;` +
|
||||
`array = *;` +
|
||||
`nil = ;` +
|
||||
`empty = *:nil;` +
|
||||
`datafmt.T4 = "<" (a:empty {a / ", "} | "-") ">" `
|
||||
|
||||
func TestStruct4(t *testing.T) {
|
||||
x := 7
|
||||
check(t, F4a, "<->", T4{nil, nil})
|
||||
check(t, F4a, "<7>", T4{&x, nil})
|
||||
check(t, F4b, "<->", T4{nil, nil})
|
||||
check(t, F4b, "<2, 3, 7>", T4{nil, []int{2, 3, 7}})
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting a struct (documentation example)
|
||||
|
||||
type Point struct {
|
||||
name string
|
||||
x, y int
|
||||
}
|
||||
|
||||
const FPoint = `datafmt "datafmt";` +
|
||||
`int = "%d";` +
|
||||
`hexInt = "0x%x";` +
|
||||
`string = "---%s---";` +
|
||||
`datafmt.Point = name "{" x ", " y:hexInt "}";`
|
||||
|
||||
func TestStructPoint(t *testing.T) {
|
||||
p := Point{"foo", 3, 15}
|
||||
check(t, FPoint, "---foo---{3, 0xf}", p)
|
||||
}
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Formatting a slice (documentation example)
|
||||
|
||||
const FSlice = `int = "%b";` +
|
||||
`array = { * / ", " }`
|
||||
|
||||
func TestSlice(t *testing.T) { check(t, FSlice, "10, 11, 101, 111", []int{2, 3, 5, 7}) }
|
||||
|
||||
// TODO add more tests
|
||||
@ -1,368 +0,0 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package datafmt
|
||||
|
||||
import (
|
||||
"go/scanner"
|
||||
"go/token"
|
||||
"os"
|
||||
"strconv"
|
||||
"strings"
|
||||
)
|
||||
|
||||
// ----------------------------------------------------------------------------
|
||||
// Parsing
|
||||
|
||||
type parser struct {
|
||||
scanner.ErrorVector
|
||||
scanner scanner.Scanner
|
||||
file *token.File
|
||||
pos token.Pos // token position
|
||||
tok token.Token // one token look-ahead
|
||||
lit string // token literal
|
||||
|
||||
packs map[string]string // PackageName -> ImportPath
|
||||
rules map[string]expr // RuleName -> Expression
|
||||
}
|
||||
|
||||
func (p *parser) next() {
|
||||
p.pos, p.tok, p.lit = p.scanner.Scan()
|
||||
switch p.tok {
|
||||
case token.CHAN, token.FUNC, token.INTERFACE, token.MAP, token.STRUCT:
|
||||
// Go keywords for composite types are type names
|
||||
// returned by reflect. Accept them as identifiers.
|
||||
p.tok = token.IDENT // p.lit is already set correctly
|
||||
}
|
||||
}
|
||||
|
||||
func (p *parser) init(fset *token.FileSet, filename string, src []byte) {
|
||||
p.ErrorVector.Reset()
|
||||
p.file = fset.AddFile(filename, fset.Base(), len(src))
|
||||
p.scanner.Init(p.file, src, p, scanner.AllowIllegalChars) // return '@' as token.ILLEGAL w/o error message
|
||||
p.next() // initializes pos, tok, lit
|
||||
p.packs = make(map[string]string)
|
||||
p.rules = make(map[string]expr)
|
||||
}
|
||||
|
||||
func (p *parser) error(pos token.Pos, msg string) {
|
||||
p.Error(p.file.Position(pos), msg)
|
||||
}
|
||||
|
||||
func (p *parser) errorExpected(pos token.Pos, msg string) {
|
||||
msg = "expected " + msg
|
||||
if pos == p.pos {
|
||||
// the error happened at the current position;
|
||||
// make the error message more specific
|
||||
msg += ", found '" + p.tok.String() + "'"
|
||||
if p.tok.IsLiteral() {
|
||||
msg += " " + p.lit
|
||||
}
|
||||
}
|
||||
p.error(pos, msg)
|
||||
}
|
||||
|
||||
func (p *parser) expect(tok token.Token) token.Pos {
|
||||
pos := p.pos
|
||||
if p.tok != tok {
|
||||
p.errorExpected(pos, "'"+tok.String()+"'")
|
||||
}
|
||||
p.next() // make progress in any case
|
||||
return pos
|
||||
}
|
||||
|
||||
func (p *parser) parseIdentifier() string {
|
||||
name := p.lit
|
||||
p.expect(token.IDENT)
|
||||
return name
|
||||
}
|
||||
|
||||
func (p *parser) parseTypeName() (string, bool) {
|
||||
pos := p.pos
|
||||
name, isIdent := p.parseIdentifier(), true
|
||||
if p.tok == token.PERIOD {
|
||||
// got a package name, lookup package
|
||||
if importPath, found := p.packs[name]; found {
|
||||
name = importPath
|
||||
} else {
|
||||
p.error(pos, "package not declared: "+name)
|
||||
}
|
||||
p.next()
|
||||
name, isIdent = name+"."+p.parseIdentifier(), false
|
||||
}
|
||||
return name, isIdent
|
||||
}
|
||||
|
||||
// Parses a rule name and returns it. If the rule name is
|
||||
// a package-qualified type name, the package name is resolved.
|
||||
// The 2nd result value is true iff the rule name consists of a
|
||||
// single identifier only (and thus could be a package name).
|
||||
//
|
||||
func (p *parser) parseRuleName() (string, bool) {
|
||||
name, isIdent := "", false
|
||||
switch p.tok {
|
||||
case token.IDENT:
|
||||
name, isIdent = p.parseTypeName()
|
||||
case token.DEFAULT:
|
||||
name = "default"
|
||||
p.next()
|
||||
case token.QUO:
|
||||
name = "/"
|
||||
p.next()
|
||||
default:
|
||||
p.errorExpected(p.pos, "rule name")
|
||||
p.next() // make progress in any case
|
||||
}
|
||||
return name, isIdent
|
||||
}
|
||||
|
||||
func (p *parser) parseString() string {
|
||||
s := ""
|
||||
if p.tok == token.STRING {
|
||||
s, _ = strconv.Unquote(p.lit)
|
||||
// Unquote may fail with an error, but only if the scanner found
|
||||
// an illegal string in the first place. In this case the error
|
||||
// has already been reported.
|
||||
p.next()
|
||||
return s
|
||||
} else {
|
||||
p.expect(token.STRING)
|
||||
}
|
||||
return s
|
||||
}
|
||||
|
||||
func (p *parser) parseLiteral() literal {
|
||||
s := []byte(p.parseString())
|
||||
|
||||
// A string literal may contain %-format specifiers. To simplify
|
||||
// and speed up printing of the literal, split it into segments
|
||||
// that start with "%" possibly followed by a last segment that
|
||||
// starts with some other character.
|
||||
var list []interface{}
|
||||
i0 := 0
|
||||
for i := 0; i < len(s); i++ {
|
||||
if s[i] == '%' && i+1 < len(s) {
|
||||
// the next segment starts with a % format
|
||||
if i0 < i {
|
||||
// the current segment is not empty, split it off
|
||||
list = append(list, s[i0:i])
|
||||
i0 = i
|
||||
}
|
||||
i++ // skip %; let loop skip over char after %
|
||||
}
|
||||
}
|
||||
// the final segment may start with any character
|
||||
// (it is empty iff the string is empty)
|
||||
list = append(list, s[i0:])
|
||||
|
||||
// convert list into a literal
|
||||
lit := make(literal, len(list))
|
||||
for i := 0; i < len(list); i++ {
|
||||
lit[i] = list[i].([]byte)
|
||||
}
|
||||
|
||||
return lit
|
||||
}
|
||||
|
||||
func (p *parser) parseField() expr {
|
||||
var fname string
|
||||
switch p.tok {
|
||||
case token.ILLEGAL:
|
||||
if p.lit != "@" {
|
||||
return nil
|
||||
}
|
||||
fname = "@"
|
||||
p.next()
|
||||
case token.MUL:
|
||||
fname = "*"
|
||||
p.next()
|
||||
case token.IDENT:
|
||||
fname = p.parseIdentifier()
|
||||
default:
|
||||
return nil
|
||||
}
|
||||
|
||||
var ruleName string
|
||||
if p.tok == token.COLON {
|
||||
p.next()
|
||||
ruleName, _ = p.parseRuleName()
|
||||
}
|
||||
|
||||
return &field{fname, ruleName}
|
||||
}
|
||||
|
||||
func (p *parser) parseOperand() (x expr) {
|
||||
switch p.tok {
|
||||
case token.STRING:
|
||||
x = p.parseLiteral()
|
||||
|
||||
case token.LPAREN:
|
||||
p.next()
|
||||
x = p.parseExpression()
|
||||
if p.tok == token.SHR {
|
||||
p.next()
|
||||
x = &group{x, p.parseExpression()}
|
||||
}
|
||||
p.expect(token.RPAREN)
|
||||
|
||||
case token.LBRACK:
|
||||
p.next()
|
||||
x = &option{p.parseExpression()}
|
||||
p.expect(token.RBRACK)
|
||||
|
||||
case token.LBRACE:
|
||||
p.next()
|
||||
x = p.parseExpression()
|
||||
var div expr
|
||||
if p.tok == token.QUO {
|
||||
p.next()
|
||||
div = p.parseExpression()
|
||||
}
|
||||
x = &repetition{x, div}
|
||||
p.expect(token.RBRACE)
|
||||
|
||||
default:
|
||||
x = p.parseField() // may be nil
|
||||
}
|
||||
|
||||
return x
|
||||
}
|
||||
|
||||
func (p *parser) parseSequence() expr {
|
||||
var list []interface{}
|
||||
|
||||
for x := p.parseOperand(); x != nil; x = p.parseOperand() {
|
||||
list = append(list, x)
|
||||
}
|
||||
|
||||
// no need for a sequence if list.Len() < 2
|
||||
switch len(list) {
|
||||
case 0:
|
||||
return nil
|
||||
case 1:
|
||||
return list[0].(expr)
|
||||
}
|
||||
|
||||
// convert list into a sequence
|
||||
seq := make(sequence, len(list))
|
||||
for i := 0; i < len(list); i++ {
|
||||
seq[i] = list[i].(expr)
|
||||
}
|
||||
return seq
|
||||
}
|
||||
|
||||
func (p *parser) parseExpression() expr {
|
||||
var list []interface{}
|
||||
|
||||
for {
|
||||
x := p.parseSequence()
|
||||
if x != nil {
|
||||
list = append(list, x)
|
||||
}
|
||||
if p.tok != token.OR {
|
||||
break
|
||||
}
|
||||
p.next()
|
||||
}
|
||||
|
||||
// no need for an alternatives if list.Len() < 2
|
||||
switch len(list) {
|
||||
case 0:
|
||||
return nil
|
||||
case 1:
|
||||
return list[0].(expr)
|
||||
}
|
||||
|
||||
// convert list into a alternatives
|
||||
alt := make(alternatives, len(list))
|
||||
for i := 0; i < len(list); i++ {
|
||||
alt[i] = list[i].(expr)
|
||||
}
|
||||
return alt
|
||||
}
|
||||
|
||||
func (p *parser) parseFormat() {
|
||||
for p.tok != token.EOF {
|
||||
pos := p.pos
|
||||
|
||||
name, isIdent := p.parseRuleName()
|
||||
switch p.tok {
|
||||
case token.STRING:
|
||||
// package declaration
|
||||
importPath := p.parseString()
|
||||
|
||||
// add package declaration
|
||||
if !isIdent {
|
||||
p.error(pos, "illegal package name: "+name)
|
||||
} else if _, found := p.packs[name]; !found {
|
||||
p.packs[name] = importPath
|
||||
} else {
|
||||
p.error(pos, "package already declared: "+name)
|
||||
}
|
||||
|
||||
case token.ASSIGN:
|
||||
// format rule
|
||||
p.next()
|
||||
x := p.parseExpression()
|
||||
|
||||
// add rule
|
||||
if _, found := p.rules[name]; !found {
|
||||
p.rules[name] = x
|
||||
} else {
|
||||
p.error(pos, "format rule already declared: "+name)
|
||||
}
|
||||
|
||||
default:
|
||||
p.errorExpected(p.pos, "package declaration or format rule")
|
||||
p.next() // make progress in any case
|
||||
}
|
||||
|
||||
if p.tok == token.SEMICOLON {
|
||||
p.next()
|
||||
} else {
|
||||
break
|
||||
}
|
||||
}
|
||||
p.expect(token.EOF)
|
||||
}
|
||||
|
||||
func remap(p *parser, name string) string {
|
||||
i := strings.Index(name, ".")
|
||||
if i >= 0 {
|
||||
packageName, suffix := name[0:i], name[i:]
|
||||
// lookup package
|
||||
if importPath, found := p.packs[packageName]; found {
|
||||
name = importPath + suffix
|
||||
} else {
|
||||
var invalidPos token.Position
|
||||
p.Error(invalidPos, "package not declared: "+packageName)
|
||||
}
|
||||
}
|
||||
return name
|
||||
}
|
||||
|
||||
// Parse parses a set of format productions from source src. Custom
|
||||
// formatters may be provided via a map of formatter functions. If
|
||||
// there are no errors, the result is a Format and the error is nil.
|
||||
// Otherwise the format is nil and a non-empty ErrorList is returned.
|
||||
//
|
||||
func Parse(fset *token.FileSet, filename string, src []byte, fmap FormatterMap) (Format, os.Error) {
|
||||
// parse source
|
||||
var p parser
|
||||
p.init(fset, filename, src)
|
||||
p.parseFormat()
|
||||
|
||||
// add custom formatters, if any
|
||||
for name, form := range fmap {
|
||||
name = remap(&p, name)
|
||||
if _, found := p.rules[name]; !found {
|
||||
p.rules[name] = &custom{name, form}
|
||||
} else {
|
||||
var invalidPos token.Position
|
||||
p.Error(invalidPos, "formatter already declared: "+name)
|
||||
}
|
||||
}
|
||||
|
||||
return p.rules, p.GetError(scanner.NoMultiples)
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user