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reply Eldar Insafutdinov <e.insafutdinov gmail.com> writes:
Currently we have ParameterTypeTuple for extracting type list of function
arguments. This is not enough. There should be a clean way to extract storage
classes and default arguments if there are any. Any thoughts?
Dec 25 2009
next sibling parent "Denis Koroskin" <2korden gmail.com> writes:
On Fri, 25 Dec 2009 17:19:42 +0300, Eldar Insafutdinov  
<e.insafutdinov gmail.com> wrote:

 Currently we have ParameterTypeTuple for extracting type list of  
 function arguments. This is not enough. There should be a clean way to  
 extract storage classes and default arguments if there are any. Any  
 thoughts?

I guess you must parse string representation of the function to get everythig you need as of now. I know someone already did this and posted his code on dsource.org, but I can't tell where exactly I saw it out of my head. If you decide to make your own implementation, here is a start: struct Foo { } void bar(ref Foo foo, int i = 42) { } void Inspect(T)(T t) { pragma(msg, T.stringof); } void main() { Inspect(&bar); } Output: void function(ref Foo foo, int i = 42) Note that function properties are *extremely* bugged ATM - compiler mistakenly thinks that "bar" and typeof(bar)", or "bar.stringof" and "bar().stringof" are interchangeable (omissible parens hell). For example: template ToString(alias func) { pragma(msg, typeof(func).stringof); enum ToString = typeof(func).stringof; } void main() { enum s = ToString!(bar); } results in the following output: test.d(11): Error: expected 2 function arguments, not 0 (void(ref Foo foo, int i = 42))() // TADAM! test.d(12): Error: expected 2 function arguments, not 0 test.d(17): Error: template instance test.ToString!(bar) error instantiating This one will hopefully resolved once property feature gets implemented and omissible parens will go away.
Dec 25 2009
prev sibling next sibling parent Daniel Keep <daniel.keep.lists gmail.com> writes:
Eldar Insafutdinov wrote:
 Currently we have ParameterTypeTuple for extracting type list of function
arguments. This is not enough. There should be a clean way to extract storage
classes and default arguments if there are any. Any thoughts?

This might help. http://gist.github.com/263832
Dec 25 2009
prev sibling next sibling parent downs <default_357-line yahoo.de> writes:
Eldar Insafutdinov wrote:
 Currently we have ParameterTypeTuple for extracting type list of function
arguments. This is not enough. There should be a clean way to extract storage
classes and default arguments if there are any. Any thoughts?

Parsing stringof is not required. There's a trick (see tools.base.[isRef, refToParamList, refToValueList]) that involves "sliding" a constant value over the parameter list and seeing if it works (if not, it's ref). ------------------- Example usage: struct YWrapper(C) { C callable; alias Ret!(C) R; mixin("R opCall("~ refToParamList("" /* no leading parameter */, "Params!(C)[1 .. $]" /* types to check */, isRef!(C)[1 .. $] /* refness string */)~ ") { return callable(&opCall"~ refToValueList("," /* &opCall comes first, lead with comma */, isRef!(C)[1 .. $])~ "); }" ); } ------------------- The complete relevant code: struct __isRef(C, size_t which) { alias ParameterTypeTuple!(C) pt; pt[0..which] pre; const pt[which] test; pt[which+1..$] post; const bool r = !is(typeof(C(pre, test, post))); } template _isRef(C, size_t which) { static if (__isRef!(C, which).r) const char _isRef='t'; else const char _isRef='f'; } string refliteral(int len) { char[] res; for (int i=0; i<len; ++i) { res~="~_isRef!(C, "~ctToString(i)~")"; } return "\"\""~res; } template isRef(C) { const string isRef=mixin(refliteral(Params!(C).length)); } string refToParamList(string lead, string TUP, string refs) { string res; for (int i=0; i<refs.length; ++i) { if (refs[i]=='t') res~="ref "; res~=TUP~"["~ctToString(i)~"] param_"~ctToString(i); if (i<refs.length-1) res~=", "; } return res; } string refToValueList(string lead, string refs) { string res=""; for (int i=0; i<refs.length; ++i) { if (i) res ~= ", "; else res ~= lead; res~="param_"~ctToString(i); } return res; }
Dec 26 2009
prev sibling parent Lutger <lutger.blijdestijn gmail.com> writes:
On 12/25/2009 03:19 PM, Eldar Insafutdinov wrote:
 Currently we have ParameterTypeTuple for extracting type list of function
arguments. This is not enough. There should be a clean way to extract storage
classes and default arguments if there are any. Any thoughts?

In addition we need to be able to get the overloads for non-virtual functions.
Dec 27 2009