Rietveld Code Review Tool
Help | Bug tracker | Discussion group | Source code | Sign in
(1725)

Side by Side Diff: src/pkg/builtin/builtin.go

Issue 4907041: code review 4907041: builtin: add documentation for builtins (Closed)
Patch Set: Created 12 years, 7 months ago
Left:
Right:
Use n/p to move between diff chunks; N/P to move between comments. Please Sign in to add in-line comments.
Jump to:
View unified diff | Download patch
« no previous file with comments | « no previous file | no next file » | no next file with comments »
Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
OLDNEW
(Empty)
1 // Copyright 2011 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 /*
6 Package builtin provides documentation for Go's built-in functions.
7 The functions documented here are not actually in package builtin
8 but their descriptions here allow godoc to present documentation
9 for the language's special functions.
10 */
11 package builtin
12
13 // AnyType is here for the purposes of documentation only. It is a stand-in
dsymonds 2011/08/15 03:19:35 rouge double-space after period
14 // for any Go type, but represents the same type for any given function
15 // invocation.
16 type AnyType int
dsymonds 2011/08/15 03:19:35 did you consider using "T" as the name for this?
r 2011/08/15 03:31:43 The unsafe package uses "ArbitraryType", which is
niemeyer 2011/08/15 03:38:24 This is definitely subjective, but I find it diffi
epaz1733 2021/10/20 08:03:05 Done.
mithunshope 2023/01/18 12:57:24 Done.
17
18 // IntegerType is here for the purposes of documentation only. It is a stand-in
19 // for any integer type: int, uint int8 etc.
20 type IntegerType int
21
22 // FloatType is here for the purposes of documentation only. It is a stand-in
23 // for either float type: float32 or float64.
24 type FloatType int
25
26 // ComplexType is here for the purposes of documentation only. It is a
27 // stand-in for either complex type: complex64 or complex128.
28 type ComplexType int
29
30 // The append built-in function appends elements to the end of a slice. If
31 // it has sufficient capacity, the destination is resliced to accommodate the
32 // new elements. If it does not, a new slice (and underlying array) will be
niemeyer 2011/08/15 03:38:24 I believe a new slice will be allocated either way
33 // allocated. Append returns the updated slice. It is therefore necessary
34 // to store the result of append, often in the variable holding the slice
35 // itself:
36 // slice = append(slice, elem1, elem2)
37 // slice = appedn(slice, anotherSlice...)
38 func append(slice []AnyType, elems ...AnyType) []AnyType
39
40 // The copy built-in function copies elements from a source slice into a
41 // destination slice. (As a special case, it also will copy bytes from a
niemeyer 2011/08/15 03:38:24 I didn't know that.. good to have docs.
42 // string to a slice of bytes.) The source and destination may overlap. Copy
43 // returns the number of elements copied, which will be the minimum of
44 // len(src) and len(dst).
45 func copy(dst, src []AnyType) int
46
47 // The len built-in function returns the length of v, according to its type:
48 // Array, slice, or map: the number of elements in v.
49 // Pointer to array: the number of elements in *v.
50 // String: the number of byes in v.
niemeyer 2011/08/15 03:38:24 Typo
mithunshope 2023/01/18 12:57:24 Done.
51 // Channel: the number of elements queued (unread) in the channel buffer.
52 func len(v AnyType) int
dsymonds 2011/08/15 03:19:35 want to call out the cases for nil values?
53
54 // The cap built-in function returns the capacity of v, according to its type:
55 // Array: the number of elements in v (same as len(v)).
56 // Pointer to array: the number of elements in *v (same as len(v)).
57 // Slice: the maximum length the slice can reach when resliced.
58 // Channel: the maximum channel buffer capacity, in units of elements.
59 func cap(v AnyType) int
60
61 // The make built-in function allocates and initializes an object of type
62 // slice, map, or chan (only). Like new, the first argument is a type, not a
63 // value. Unlike new, make's return type is the same as the type of its
64 // argument, not a pointer to it. The specification of the result depends on
65 // the type:
66 // Slice: The size specifies the length. The capacity of the slice is
67 // equal to its length. A second integer argument may be provided to
68 // specify a different capacity; it must be no smaller than the
69 // length, so make([]int, 0, 10) allocates a slice of length 0 and
70 // capacity 10.
71 // Map: An initial allocation is made according to the size but the
72 // resulting map has length 0. The size may be omitted, in which case
dsymonds 2011/08/15 03:19:35 double space
73 // a small starting size is allocated.
74 // Chan: The channel's buffer is initialized with the specified buffer
dsymonds 2011/08/15 03:19:35 s/Chan/Channel/, like len and cap.
75 // capacity. If zero, or the size is omitted, the channel is
dsymonds 2011/08/15 03:19:35 double space
76 // unbuffered.
77 func make(AnyType, size IntegerType) AnyType
78
79 // The new built-in function allocates memory. The first argument is a type,
dsymonds 2011/08/15 03:19:35 double space
80 // not a value, and the value returned is a pointer to a newly
81 // allocated zero value of that type.
82 func new(AnyType) *AnyType
83
84 // The complex built-in function constructs a complex value from two
85 // floating-point values. The real and imaginary parts must be of the same
86 // size, either float32 or float64 (or assignable to them), and the return
87 // value will be the corresponding complex type (complex64 for float32,
88 // complex128 for float64).
89 func complex(r, i FloatType) ComplexType
90
91 // The real built-in function returns the real part of the complex number c.
92 // The return value will be floating point type corresponding to the type of c.
93 func real(c ComplexType) FloatType
94
95 // The imaginary built-in function returns the imaginary part of the complex
96 // number c. The return value will be floating point type corresponding to
97 // the type of c.
98 func imag(c ComplexType) FloatType
99
100 // The close built-in function closes a channel, which must be either
101 // bidirectional or send-only. It should be executed only by the sender,
102 // never the receiver, and has the effect of shutting down the channel after
103 // the last sent value is received. After the last value has been received
104 // from a closed channel c,
105 // x, ok := <-c
106 // will set x to the channel element's zero value and ok to false, and select
107 // clauses involving c will never execute.
108 func close(c chan AnyType)
dsymonds 2011/08/15 03:19:35 You could add a send-only annotation here; that wo
109
110 // The panic built-in function stops normal execution of the current
111 // goroutine. When a function F calls panic, normal execution of F stops
112 // immediately. Any functions whose execution was deferred by F are run in
113 // the usual way, and then F returns to its caller. To the caller G, the
114 // invocation of F then behaves like a call to panic, terminating G's
115 // execution and running any deferred functions. This continues until all
116 // functions in the executing goroutine have stopped, in reverse order. At
117 // that point, the program is terminated and the error condition is reported,
118 // including the value of the argument to panic. This termination sequence
119 // is called panicking and can be controlled by the built-in function
120 // recover.
121 func panic(v interface{})
122
123 // The recover built-in function allows a program to manage behavior of a
124 // panicking goroutine. Executing a call to recover inside a deferred
125 // function (but not any function called by it) stops the panicking sequence
126 // by restoring normal execution and retrieves the error value passed to the
127 // call of panic. If recover is called outside the deferred function it will
128 // not stop a panicking sequence. In this case, or when the goroutine is not
129 // panicking, or if the argument supplied to panic was nil, recover returns
130 // nil. Thus the return value from recover reports whether the goroutine is
131 // panicking.
132 func recover() interface{}
OLDNEW
« no previous file with comments | « no previous file | no next file » | no next file with comments »

Powered by Google App Engine
RSS Feeds Recent Issues | This issue
This is Rietveld f62528b