digitalmars.D.learn - about std.string.representation
- bioinfornatics (27/27) Nov 13 2013 Hi,
- bearophile (5/6) Nov 13 2013 sizeof of a dynamic array always gives 2 * size_t.sizeof = 8 or
- Jared Miller (18/18) Nov 13 2013 To expand on bearophile's answer, a dynamic array is basically a
- =?UTF-8?B?QWxpIMOHZWhyZWxp?= (26/29) Nov 14 2013 And for templates, there is std.range.ElementEncodingType:
- bioinfornatics (14/43) Nov 18 2013 Thanks Ali that is interesting too …
- =?UTF-8?B?QWxpIMOHZWhyZWxp?= (23/73) Nov 18 2013 I don't know an existing function but I think the following is what you
- bioinfornatics (17/98) Nov 19 2013 Yes that is what i want. whyu not to use a piece of code from
- bioinfornatics (17/125) Nov 19 2013 FIX
- bioinfornatics (35/35) Nov 19 2013 I try this
- bioinfornatics (34/34) Nov 19 2013 works as expected
Hi,
I try to understand which type char, dchar, wchar will give
ubyte,ushort,uint…
for this i try :
------------ CODE ---------------------
import std.string;
void main(){
string t = "test";
char[] c = "test".dup;
dchar[] dc = "test"d.dup;
wchar[] wc = "test"w.dup;
writeln( typeid( t ), ' ', t.sizeof, ' ', t.representation()
);
writeln( typeid( c ), ' ', c.sizeof, ' ', c.representation()
);
writeln( typeid( dc ), ' ', dc.sizeof, ' ', dc.representation()
);
writeln( typeid( wc ), ' ', wc.sizeof, ' ', wc.representation()
);
}
------------ RESULT ---------------------
immutable(char)[]16 [116, 101, 115, 116]
char[] 16 [116, 101, 115, 116]
dchar[] 16 [116, 101, 115, 116]
wchar[] 16 [116, 101, 115, 116]
------------------------------------------
each time it seem ushort is used someone coul explaen please?
Nov 13 2013
"bearophile" <bearophileHUGS lycos.com> bioinfornatics:each time it seem ushort is used someone coul explaen please?sizeof of a dynamic array always gives 2 * size_t.sizeof = 8 or 16 bytes. Bye, bearophile
Nov 13 2013
To expand on bearophile's answer, a dynamic array is basically a package of two things: a length and a pointer to the contents. Each of these is 8 bytes on a 64-bit system, thus the sizeof a dynamic array is 16 bytes. You are asking how char, wchar, and dchar correspond to integer types. That is defined here: http://dlang.org/type.html. char = 1 byte (ubyte) wchar = 2 bytes (ushort) dchar = 4 bytes (uint) To show this, print the sizeof an element in each of those arrays: writeln( typeid( t ), ' ', t[0].sizeof, ' ', t.representation() ); // 1 writeln( typeid( c ), ' ', c[0].sizeof, ' ', c.representation() ); // 1 writeln( typeid( dc ), ' ', dc[0].sizeof, ' ', dc.representation() ); // 4 writeln( typeid( wc ), ' ', wc[0].sizeof, ' ', wc.representation() ); // 2
Nov 13 2013
On 11/13/2013 04:32 PM, bioinfornatics wrote:Hi, I try to understand which type char, dchar, wchar will give ubyte,ushort,uint…And for templates, there is std.range.ElementEncodingType: import std.stdio; import std.range; void foo(R)(R range) { // In contrast, ElementType!R for strings is always dchar writeln(typeid(ElementEncodingType!R)); } void main() { string t = "test"; char[] c = "test".dup; dchar[] dc = "test"d.dup; wchar[] wc = "test"w.dup; foo(t); foo(c); foo(dc); foo(wc); } Prints: immutable(char) char dchar wchar Ali
Nov 14 2013
On Thursday, 14 November 2013 at 12:01:04 UTC, Ali Çehreli wrote:On 11/13/2013 04:32 PM, bioinfornatics wrote:Thanks Ali that is interesting too … In same way i would like to know if they are a function wich return ubyte, ushort, uint instead of: - char, dchar, wchar from std.range.ElementEncodingType - ubyte[], ushort[], uint[] from std.string.representation maybe: foo(T)( string s ){ alias T typeof(s.representation[0]); … … … }Hi, I try to understand which type char, dchar, wchar will give ubyte,ushort,uint…And for templates, there is std.range.ElementEncodingType: import std.stdio; import std.range; void foo(R)(R range) { // In contrast, ElementType!R for strings is always dchar writeln(typeid(ElementEncodingType!R)); } void main() { string t = "test"; char[] c = "test".dup; dchar[] dc = "test"d.dup; wchar[] wc = "test"w.dup; foo(t); foo(c); foo(dc); foo(wc); } Prints: immutable(char) char dchar wchar Ali
Nov 18 2013
On 11/18/2013 07:48 PM, bioinfornatics wrote:On Thursday, 14 November 2013 at 12:01:04 UTC, Ali Çehreli wrote:I don't know an existing function but I think the following is what you are looking for: import std.range; template NonUtfElementEncodingType(S) { alias ET = ElementEncodingType!S; static if (is (ET == char)) { alias NonUtfElementEncodingType = ubyte; } else static if (is (ET == wchar)) { alias NonUtfElementEncodingType = ushort; } else static if (is (ET == dchar)) { alias NonUtfElementEncodingType = uint; } else { alias NonUtfElementEncodingType = ET; } } void main() { alias Foo = NonUtfElementEncodingType!string; Foo[] myByteArray; } AliOn 11/13/2013 04:32 PM, bioinfornatics wrote:Thanks Ali that is interesting too … In same way i would like to know if they are a function wich return ubyte, ushort, uint instead of: - char, dchar, wchar from std.range.ElementEncodingType - ubyte[], ushort[], uint[] from std.string.representation maybe: foo(T)( string s ){ alias T typeof(s.representation[0]); … … … }Hi, I try to understand which type char, dchar, wchar will give ubyte,ushort,uint…And for templates, there is std.range.ElementEncodingType: import std.stdio; import std.range; void foo(R)(R range) { // In contrast, ElementType!R for strings is always dchar writeln(typeid(ElementEncodingType!R)); } void main() { string t = "test"; char[] c = "test".dup; dchar[] dc = "test"d.dup; wchar[] wc = "test"w.dup; foo(t); foo(c); foo(dc); foo(wc); } Prints: immutable(char) char dchar wchar Ali
Nov 18 2013
On Tuesday, 19 November 2013 at 06:11:26 UTC, Ali Çehreli wrote:On 11/18/2013 07:48 PM, bioinfornatics wrote:Yes that is what i want. whyu not to use a piece of code from std.string.representation ? auto CharEncodingType(Char)(Char[] s) pure nothrow if(isSomeChar!Char) { // Get representation type alias TypeTuple!(ubyte, ushort, uint)U; // const and immutable storage classes static if (is(Char == immutable)) alias immutable(U) T; else static if (is(Char == const)) alias const(U) T; else alias U T; // shared storage class (because shared(const(T)) is possible) static if (is(Char == shared)) alias shared(T) ST; else alias T ST; return cast(ST) s; }On Thursday, 14 November 2013 at 12:01:04 UTC, Ali Çehreli wrote:I don't know an existing function but I think the following is what you are looking for: import std.range; template NonUtfElementEncodingType(S) { alias ET = ElementEncodingType!S; static if (is (ET == char)) { alias NonUtfElementEncodingType = ubyte; } else static if (is (ET == wchar)) { alias NonUtfElementEncodingType = ushort; } else static if (is (ET == dchar)) { alias NonUtfElementEncodingType = uint; } else { alias NonUtfElementEncodingType = ET; } } void main() { alias Foo = NonUtfElementEncodingType!string; Foo[] myByteArray; } AliOn 11/13/2013 04:32 PM, bioinfornatics wrote:Thanks Ali that is interesting too … In same way i would like to know if they are a function wich return ubyte, ushort, uint instead of: - char, dchar, wchar from std.range.ElementEncodingType - ubyte[], ushort[], uint[] from std.string.representation maybe: foo(T)( string s ){ alias T typeof(s.representation[0]); … … … }Hi, I try to understand which type char, dchar, wchar will give ubyte,ushort,uint…And for templates, there is std.range.ElementEncodingType: import std.stdio; import std.range; void foo(R)(R range) { // In contrast, ElementType!R for strings is always dchar writeln(typeid(ElementEncodingType!R)); } void main() { string t = "test"; char[] c = "test".dup; dchar[] dc = "test"d.dup; wchar[] wc = "test"w.dup; foo(t); foo(c); foo(dc); foo(wc); } Prints: immutable(char) char dchar wchar Ali
Nov 19 2013
On Tuesday, 19 November 2013 at 23:53:33 UTC, bioinfornatics wrote:On Tuesday, 19 November 2013 at 06:11:26 UTC, Ali Çehreli wrote:FIX template CharEncodingType(Char[] s) pure nothrow if(isSomeChar!Char) { // Get representation type alias TypeTuple!(ubyte, ushort, uint)[Char.sizeof / 2] U; // const and immutable storage classes static if (is(Char == immutable)) alias immutable(U) T; else static if (is(Char == const)) alias const(U) T; else alias U T; // shared storage class (because shared(const(T)) is possible) static if (is(Char == shared)) alias shared(T) CharEncodingType; else alias T CharEncodingType; }On 11/18/2013 07:48 PM, bioinfornatics wrote:Yes that is what i want. whyu not to use a piece of code from std.string.representation ? auto CharEncodingType(Char)(Char[] s) pure nothrow if(isSomeChar!Char) { // Get representation type alias TypeTuple!(ubyte, ushort, uint)U; // const and immutable storage classes static if (is(Char == immutable)) alias immutable(U) T; else static if (is(Char == const)) alias const(U) T; else alias U T; // shared storage class (because shared(const(T)) is possible) static if (is(Char == shared)) alias shared(T) ST; else alias T ST; return cast(ST) s; }On Thursday, 14 November 2013 at 12:01:04 UTC, Ali Çehreli wrote:I don't know an existing function but I think the following is what you are looking for: import std.range; template NonUtfElementEncodingType(S) { alias ET = ElementEncodingType!S; static if (is (ET == char)) { alias NonUtfElementEncodingType = ubyte; } else static if (is (ET == wchar)) { alias NonUtfElementEncodingType = ushort; } else static if (is (ET == dchar)) { alias NonUtfElementEncodingType = uint; } else { alias NonUtfElementEncodingType = ET; } } void main() { alias Foo = NonUtfElementEncodingType!string; Foo[] myByteArray; } AliOn 11/13/2013 04:32 PM, bioinfornatics wrote:Thanks Ali that is interesting too … In same way i would like to know if they are a function wich return ubyte, ushort, uint instead of: - char, dchar, wchar from std.range.ElementEncodingType - ubyte[], ushort[], uint[] from std.string.representation maybe: foo(T)( string s ){ alias T typeof(s.representation[0]); … … … }Hi, I try to understand which type char, dchar, wchar will give ubyte,ushort,uint…And for templates, there is std.range.ElementEncodingType: import std.stdio; import std.range; void foo(R)(R range) { // In contrast, ElementType!R for strings is always dchar writeln(typeid(ElementEncodingType!R)); } void main() { string t = "test"; char[] c = "test".dup; dchar[] dc = "test"d.dup; wchar[] wc = "test"w.dup; foo(t); foo(c); foo(dc); foo(wc); } Prints: immutable(char) char dchar wchar Ali
Nov 19 2013
I try this
import std.traits : isSomeChar;
import std.typetuple : TypeTuple;
import std.stdio;
template CharEncodingType(Char)
{
// Get representation type
alias TypeTuple!(ubyte, ushort, uint) U;
// const and immutable storage classes
static if (is(Char == immutable)) alias immutable(U) T;
else static if (is(Char == const)) alias const(U) T;
else alias U T;
// shared storage class (because shared(const(T)) is possible)
static if (is(Char == shared)) alias shared(T)
CharEncodingType;
else alias T CharEncodingType;
}
void main()
{
string t = "test";
char[] c = "test".dup;
dchar[] dc = "test"d.dup;
wchar[] wc = "test"w.dup;
alias T = CharEncodingType!(typeof(t));
alias C = CharEncodingType!(typeof(c));
alias DC = CharEncodingType!(typeof(dc));
alias WC = CharEncodingType!(typeof(wc));
writeln( typeid(T), typeid(C), typeid(DC), typeid(WC) );
}
RESULT
$ ~/test_type
(ubyte,ushort,uint)(ubyte,ushort,uint)(ubyte,ushort,uint)(ubyte,ushort,uint)
instead of ubyte,ushort,uint
i will use your way ali
thanks for your useful code
Nov 19 2013
works as expected
import std.traits : isSomeChar;
import std.range : ElementEncodingType;
import std.stdio;
safe pure nothrow
template CharEncodingType(Char)
{
alias ET = ElementEncodingType!Char;
static if (is (ET == char)) {
alias CharEncodingType = ubyte;
} else static if (is (ET == wchar)) {
alias CharEncodingType = ushort;
} else static if (is (ET == dchar)) {
alias CharEncodingType = uint;
} else {
alias CharEncodingType = ET;
}
}
void main()
{
string t = "test";
char[] c = "test".dup;
dchar[] dc = "test"d.dup;
wchar[] wc = "test"w.dup;
alias T = CharEncodingType!(typeof(t));
alias C = CharEncodingType!(typeof(c));
alias DC = CharEncodingType!(typeof(dc));
alias WC = CharEncodingType!(typeof(wc));
writeln( typeid(T), ' ', typeid(C), ' ', typeid(DC), ' ',
typeid(WC) );
}
Result
immutable(char) ubyte uint ushort
thanks all
Nov 19 2013