mirror of
https://github.com/golang/go
synced 2024-11-11 23:20:24 -07:00
go_tutorial: removed outdated use of semicolons
R=r CC=golang-dev https://golang.org/cl/1013042
This commit is contained in:
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69a2e1dc52
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@ -184,7 +184,7 @@ string variable we will use to build the output.
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The declaration statement has the form
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<p>
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<pre>
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var s string = "";
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var s string = ""
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</pre>
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<p>
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This is the <code>var</code> keyword, followed by the name of the variable, followed by
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@ -195,13 +195,13 @@ string constant is of type string, we don't have to tell the compiler that.
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We could write
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<p>
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<pre>
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var s = "";
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var s = ""
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</pre>
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<p>
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or we could go even shorter and write the idiom
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<p>
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<pre>
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s := "";
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s := ""
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</pre>
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<p>
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The <code>:=</code> operator is used a lot in Go to represent an initializing declaration.
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@ -264,8 +264,8 @@ However the following statements are illegal because they would modify
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a <code>string</code> value:
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<p>
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<pre>
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s[0] = 'x';
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(*p)[1] = 'y';
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s[0] = 'x'
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(*p)[1] = 'y'
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</pre>
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<p>
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In C++ terms, Go strings are a bit like <code>const strings</code>, while pointers
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@ -277,7 +277,7 @@ read on.
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Arrays are declared like this:
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<p>
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<pre>
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var arrayOfInt [10]int;
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var arrayOfInt [10]int
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</pre>
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<p>
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Arrays, like strings, are values, but they are mutable. This differs
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@ -341,7 +341,7 @@ If you are creating a regular array but want the compiler to count the
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elements for you, use <code>...</code> as the array size:
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<p>
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<pre>
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s := sum(&[...]int{1,2,3});
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s := sum(&[...]int{1,2,3})
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</pre>
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<p>
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In practice, though, unless you're meticulous about storage layout within a
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@ -349,7 +349,7 @@ data structure, a slice itself—using empty brackets and no
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<code>&</code>—is all you need:
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<p>
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<pre>
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s := sum([]int{1,2,3});
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s := sum([]int{1,2,3})
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</pre>
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<p>
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There are also maps, which you can initialize like this:
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@ -391,13 +391,13 @@ returns a pointer to the allocated storage.
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<p>
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<pre>
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type T struct { a, b int }
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var t *T = new(T);
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var t *T = new(T)
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</pre>
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<p>
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or the more idiomatic
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<p>
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<pre>
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t := new(T);
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t := new(T)
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</pre>
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<p>
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Some types—maps, slices, and channels (see below)—have reference semantics.
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@ -406,14 +406,14 @@ referencing the same underlying data will see the modification. For these three
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types you want to use the built-in function <code>make()</code>:
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<p>
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<pre>
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m := make(map[string]int);
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m := make(map[string]int)
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</pre>
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<p>
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This statement initializes a new map ready to store entries.
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If you just declare the map, as in
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<p>
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<pre>
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var m map[string]int;
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var m map[string]int
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</pre>
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<p>
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it creates a <code>nil</code> reference that cannot hold anything. To use the map,
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@ -518,9 +518,9 @@ the ones used to build maps and arrays, to construct a new heap-allocated
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object. We could write
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<p>
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<pre>
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n := new(File);
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n.fd = fd;
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n.name = name;
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n := new(File)
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n.fd = fd
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n.name = name
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return n
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</pre>
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<p>
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@ -640,7 +640,7 @@ We can now use our new package:
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11 )
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<p>
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13 func main() {
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14 hello := []byte{'h', 'e', 'l', 'l', 'o', ',', ' ', 'w', 'o', 'r', 'l', 'd', '\n'}
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14 hello := []byte("hello, world\n")
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15 file.Stdout.Write(hello)
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16 file, err := file.Open("/does/not/exist", 0, 0)
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17 if file == nil {
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@ -903,7 +903,7 @@ to test that the result is sorted.
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14 a := sort.IntArray(data)
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15 sort.Sort(a)
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16 if !sort.IsSorted(a) {
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17 panic()
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17 panic("fail")
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18 }
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19 }
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</pre>
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@ -1050,7 +1050,7 @@ Schematically, given a value <code>v</code>, it does this:
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</pre>
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<p>
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<pre>
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s, ok := v.(Stringer); // Test whether v implements "String()"
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s, ok := v.(Stringer) // Test whether v implements "String()"
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if ok {
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result = s.String()
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} else {
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@ -1077,7 +1077,7 @@ interface type defined in the <code>io</code> library:
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<p>
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<pre>
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type Writer interface {
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Write(p []byte) (n int, err os.Error);
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Write(p []byte) (n int, err os.Error)
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}
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</pre>
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<p>
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@ -1162,17 +1162,17 @@ this starts the function running in parallel with the current
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computation but in the same address space:
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<p>
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<pre>
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go sum(hugeArray); // calculate sum in the background
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go sum(hugeArray) // calculate sum in the background
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</pre>
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<p>
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If you want to know when the calculation is done, pass a channel
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on which it can report back:
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<p>
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<pre>
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ch := make(chan int);
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go sum(hugeArray, ch);
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ch := make(chan int)
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go sum(hugeArray, ch)
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// ... do something else for a while
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result := <-ch; // wait for, and retrieve, result
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result := <-ch // wait for, and retrieve, result
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</pre>
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<p>
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Back to our prime sieve. Here's how the sieve pipeline is stitched
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@ -143,7 +143,7 @@ string variable we will use to build the output.
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The declaration statement has the form
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var s string = "";
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var s string = ""
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This is the "var" keyword, followed by the name of the variable, followed by
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its type, followed by an equals sign and an initial value for the variable.
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@ -152,11 +152,11 @@ Go tries to be terse, and this declaration could be shortened. Since the
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string constant is of type string, we don't have to tell the compiler that.
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We could write
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var s = "";
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var s = ""
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or we could go even shorter and write the idiom
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s := "";
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s := ""
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The ":=" operator is used a lot in Go to represent an initializing declaration.
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There's one in the "for" clause on the next line:
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@ -208,8 +208,8 @@ reassigning it. This snippet from "strings.go" is legal code:
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However the following statements are illegal because they would modify
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a "string" value:
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s[0] = 'x';
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(*p)[1] = 'y';
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s[0] = 'x'
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(*p)[1] = 'y'
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In C++ terms, Go strings are a bit like "const strings", while pointers
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to strings are analogous to "const string" references.
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@ -219,7 +219,7 @@ read on.
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Arrays are declared like this:
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var arrayOfInt [10]int;
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var arrayOfInt [10]int
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Arrays, like strings, are values, but they are mutable. This differs
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from C, in which "arrayOfInt" would be usable as a pointer to "int".
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@ -271,13 +271,13 @@ pointer to "sum()" by (implicitly) promoting it to a slice.
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If you are creating a regular array but want the compiler to count the
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elements for you, use "..." as the array size:
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s := sum(&[...]int{1,2,3});
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s := sum(&[...]int{1,2,3})
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In practice, though, unless you're meticulous about storage layout within a
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data structure, a slice itself—using empty brackets and no
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"&"—is all you need:
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s := sum([]int{1,2,3});
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s := sum([]int{1,2,3})
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There are also maps, which you can initialize like this:
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@ -312,23 +312,23 @@ To allocate a new variable, use "new()", which
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returns a pointer to the allocated storage.
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type T struct { a, b int }
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var t *T = new(T);
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var t *T = new(T)
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or the more idiomatic
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t := new(T);
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t := new(T)
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Some types—maps, slices, and channels (see below)—have reference semantics.
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If you're holding a slice or a map and you modify its contents, other variables
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referencing the same underlying data will see the modification. For these three
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types you want to use the built-in function "make()":
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m := make(map[string]int);
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m := make(map[string]int)
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This statement initializes a new map ready to store entries.
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If you just declare the map, as in
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var m map[string]int;
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var m map[string]int
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it creates a "nil" reference that cannot hold anything. To use the map,
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you must first initialize the reference using "make()" or by assignment from an
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@ -410,9 +410,9 @@ filled in. This code uses Go's notion of a ''composite literal'', analogous to
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the ones used to build maps and arrays, to construct a new heap-allocated
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object. We could write
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n := new(File);
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n.fd = fd;
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n.name = name;
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n := new(File)
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n.fd = fd
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n.name = name
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return n
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but for simple structures like "File" it's easier to return the address of a nonce
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@ -696,7 +696,7 @@ Schematically, given a value "v", it does this:
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String() string
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}
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s, ok := v.(Stringer); // Test whether v implements "String()"
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s, ok := v.(Stringer) // Test whether v implements "String()"
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if ok {
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result = s.String()
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} else {
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@ -721,7 +721,7 @@ not a file. Instead, it is a variable of type "io.Writer", which is an
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interface type defined in the "io" library:
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type Writer interface {
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Write(p []byte) (n int, err os.Error);
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Write(p []byte) (n int, err os.Error)
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}
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(This interface is another conventional name, this time for "Write"; there are also
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@ -787,15 +787,15 @@ invoke the function, prefixing the call with the keyword "go";
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this starts the function running in parallel with the current
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computation but in the same address space:
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go sum(hugeArray); // calculate sum in the background
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go sum(hugeArray) // calculate sum in the background
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If you want to know when the calculation is done, pass a channel
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on which it can report back:
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ch := make(chan int);
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go sum(hugeArray, ch);
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ch := make(chan int)
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go sum(hugeArray, ch)
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// ... do something else for a while
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result := <-ch; // wait for, and retrieve, result
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result := <-ch // wait for, and retrieve, result
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Back to our prime sieve. Here's how the sieve pipeline is stitched
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together:
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