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comparison d2/qtd/Meta.d @ 344:96a75b1e5b26

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project structure changes
author Max Samukha <maxter@spambox.com>
date Fri, 14 May 2010 12:14:37 +0300
parents qt/qtd/Meta.d@4e31cbd9e20c
children
comparison
equal deleted inserted replaced
343:552647ec0f82 344:96a75b1e5b26
1 module qtd.Meta;
2
3 import std.traits;
4 import std.typetuple;
5 import std.string;
6
7 // Various compile time utilities
8
9 public bool ctfeStartsWith(T)(T[] source, T[] pattern)
10 {
11 return source.length >= pattern.length && source[0 .. pattern.length] == pattern[];
12 }
13
14 // compile-time toString, maybe to!string is already working in CT
15 string __toString(long v)
16 {
17 if (v == 0)
18 return "0";
19
20 string ret;
21
22 bool neg;
23 if (v < 0)
24 {
25 neg = true;
26 v = -v;
27 }
28
29 while (v != 0)
30 {
31 ret = cast(char)(v % 10 + '0') ~ ret;
32 v = cast(long)(v / 10);
33 }
34
35 if (neg)
36 ret = "-" ~ ret;
37
38 return ret;
39 }
40
41 // returns the type of a template parameter if there is one
42 template templateParam(U : V!(U), alias V)
43 {
44 alias U templateParam;
45 }
46
47 // to workaround buggy foreach, returns a tuple of Ts of size I
48 template Repeat(T, int I)
49 {
50 static if (!I) alias TypeTuple!() Repeat;
51 else alias TypeTuple!(T, Repeat!(T, I - 1)) Repeat;
52 }
53
54 //returns number of required function arguments, optional arguments excluded
55 int requiredArgCount(alias fn)() {
56 alias ParameterTypeTuple!(typeof(&fn)) P;
57 P p;
58 static if (P.length == 0)
59 return 0;
60
61 foreach(i, _; P)
62 {
63 static if (!__traits(compiles, fn(p[0..$-i-1])))
64 {
65 return p.length - i;
66 }
67 }
68 return 0;
69 }
70
71 template isDg(Dg)
72 {
73 enum isDg = is(Dg == delegate);
74 }
75
76 template isFn(Fn)
77 {
78 enum isFn = is(typeof(*Fn.init) == function);
79 }
80
81 template isFnOrDg(Dg)
82 {
83 enum isFnOrDg = isFn!(Dg) || isDg!(Dg);
84 }
85
86 uint isModule(string str)
87 {
88 return startsWith(str, "module ");
89 }
90
91 template qualifiedCppName(T)
92 {
93 static if(!isModule(__traits(parent, T).stringof))
94 enum qualifiedCppName = qualifiedCppName!(__traits(parent, T)) ~ "::" ~ T.stringof;
95 else
96 enum qualifiedCppName = T.stringof;
97 }
98
99 template qualifiedDName(T)
100 {
101 static if (!isModule(__traits(parent, T).stringof))
102 enum qualifiedDName = qualifiedDName!(__traits(parent, T)) ~ "." ~ T.stringof;
103 else
104 enum qualifiedDName = T.stringof;
105 }
106
107 template fullDName(T)
108 {
109 static if (is(T == enum))
110 enum fullDName = qualifiedDName!T;
111 else
112 enum fullDName = T.stringof;
113 }