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- added language to document .() notation
- propose change to char/string productions: I find this easier to read SVN=116037
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@ -1,6 +1,6 @@
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The Go Programming Language
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----
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(March 28, 2008)
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(April 17, 2008)
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This document is an informal specification/proposal for a new systems programming
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language.
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@ -402,15 +402,15 @@ Character and string literals are similar to C except:
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The rules are:
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char_lit = "'" ( unicode_value | byte_value ) "'" .
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unicode_value = utf8_char | little_u_value | big_u_value | escaped_char .
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byte_value = octal_byte_value | hex_byte_value .
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octal_byte_value = "\" oct_digit oct_digit oct_digit .
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hex_byte_value = "\" "x" hex_digit hex_digit .
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little_u_value = "\" "u" hex_digit hex_digit hex_digit hex_digit .
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big_u_value = "\" "U" hex_digit hex_digit hex_digit hex_digit
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hex_digit hex_digit hex_digit hex_digit .
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escaped_char = "\" ( "a" | "b" | "f" | "n" | "r" | "t" | "v" | "\" | "'" | "\"" ) .
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char_lit = "'" ( utf8_char_no_single_quote | "\" esc_seq ) "'" .
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esc_seq =
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"a" | "b" | "f" | "n" | "r" | "t" | "v" | "\" | "'" | "\"" |
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oct_digit oct_digit oct_digit |
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"x" hex_digit hex_digit |
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"u" hex_digit hex_digit hex_digit hex_digit |
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"U" hex_digit hex_digit hex_digit hex_digit
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hex_digit hex_digit hex_digit hex_digit .
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A unicode_value takes one of four forms:
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@ -457,8 +457,8 @@ Double-quoted strings have the usual properties; back-quoted strings
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do not interpret backslashes at all.
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string_lit = raw_string_lit | interpreted_string_lit .
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raw_string_lit = "`" { utf8_char } "`" .
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interpreted_string_lit = "\"" { unicode_value | byte_value } "\"" .
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raw_string_lit = "`" { utf8_char_no_back_quote } "`" .
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interpreted_string_lit = "\"" { utf8_char_no_double_quote | "\\" esc_seq } "\"" .
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A string literal has type 'string'. Its value is constructed by
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taking the byte values formed by the successive elements of the
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@ -1078,7 +1078,8 @@ Expression syntax is based on that of C but with fewer precedence levels.
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PrimaryExpr =
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identifier | Literal | "(" Expression ")" | "iota" |
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Call | Conversion | Allocation |
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Expression "[" Expression [ ":" Expression ] "]" | Expression "." identifier .
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Expression "[" Expression [ ":" Expression ] "]" | Expression "." identifier |
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Expression "." "(" Type ")" .
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Call = Expression "(" [ ExpressionList ] ")" .
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Conversion = TypeName "(" [ ExpressionList ] ")" .
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@ -1092,8 +1093,9 @@ Expression syntax is based on that of C but with fewer precedence levels.
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unary_op = "+" | "-" | "!" | "^" | "<" | ">" | "*" | "&" .
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Field selection ('.') binds tightest, followed by indexing ('[]') and then calls and conversions.
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The remaining precedence levels are as follows (in increasing precedence order):
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Field selection and type assertions ('.') bind tightest, followed by indexing ('[]')
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and then calls and conversions. The remaining precedence levels are as follows
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(in increasing precedence order):
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Precedence Operator
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1 ||
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