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digitalmars.D - Array to variadic function?

reply bobef <bobef lessequal.com> writes:
Is there some way to pass something like array to variadic function. I 
mean often there is no variant where function take valist instead of ... 
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
	... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
	if(values.length==1) someCfunction(345,values[0].toString());
	else if(values.length==2) 
someCfunction(543,values[0].toString(),values[1].toString());
	//etc...
}

There must be a better way to do this...
Nov 28 2005
next sibling parent reply pragma <pragma_member pathlink.com> writes:
In article <dmfcgr$2hpa$1 digitaldaemon.com>, bobef says...

Is there some way to pass something like array to variadic function. I 
mean often there is no variant where function take valist instead of ... 
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
	... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
	if(values.length==1) someCfunction(345,values[0].toString());
	else if(values.length==2) 
someCfunction(543,values[0].toString(),values[1].toString());
	//etc...
}

There must be a better way to do this...


I'm shooting from the hip here, but have you tried this?

void foobar(int a,void*[]...){ /* stuff */ }

- EricAnderton at yahoo
Nov 28 2005
parent bobef <bobef lessequal.com> writes:
pragma wrote:

 In article <dmfcgr$2hpa$1 digitaldaemon.com>, bobef says...
 

Is there some way to pass something like array to variadic function. I 
mean often there is no variant where function take valist instead of ... 
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
	... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
	if(values.length==1) someCfunction(345,values[0].toString());
	else if(values.length==2) 
someCfunction(543,values[0].toString(),values[1].toString());
	//etc...
}

There must be a better way to do this...


 
 
 I'm shooting from the hip here, but have you tried this?
 
 void foobar(int a,void*[]...){ /* stuff */ }
 
 - EricAnderton at yahoo


I can't. I am not allowed to change any of the two functions. The one is 
defined by dmdscript and the other by the (guy_who_wrote_it !is me)
Dec 01 2005
prev sibling parent reply "Walter Bright" <newshound digitalmars.com> writes:
"bobef" <bobef lessequal.com> wrote in message
news:dmfcgr$2hpa$1 digitaldaemon.com...

 Is there some way to pass something like array to variadic function. I
 mean often there is no variant where function take valist instead of ...
 and when you need to wrap this function what do you do? Write many ifs?
 I will illustrate my question with example

 void someCfunction(int a,...)
 {
 ... do stuff here
 }


 void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
 {
 if(values.length==1) someCfunction(345,values[0].toString());
 else if(values.length==2)
 someCfunction(543,values[0].toString(),values[1].toString());
 //etc...
 }

 There must be a better way to do this...


Redeclare someCfunction as:

void someCfunction(int[] a ...)
Dec 01 2005
next sibling parent Ivan Senji <ivan.senji_REMOVE_ _THIS__gmail.com> writes:
Walter Bright wrote:

 "bobef" <bobef lessequal.com> wrote in message
 news:dmfcgr$2hpa$1 digitaldaemon.com...
 

Is there some way to pass something like array to variadic function. I
mean often there is no variant where function take valist instead of ...
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
if(values.length==1) someCfunction(345,values[0].toString());
else if(values.length==2)
someCfunction(543,values[0].toString(),values[1].toString());
//etc...
}

There must be a better way to do this...


 
 
 Redeclare someCfunction as:
 
 void someCfunction(int[] a ...)
 


I think the problem is you can't allways redeclare a function.
What would be nice is to be able to construct arguments and pass them to 
another function.

For example to be able to (with ...) take n arguments, and pass to 
another variadic function some of them, for example a slice.
Dec 01 2005
prev sibling parent reply bobef <bobef lessequal.com> writes:
Walter Bright wrote:

 "bobef" <bobef lessequal.com> wrote in message
 news:dmfcgr$2hpa$1 digitaldaemon.com...
 

Is there some way to pass something like array to variadic function. I
mean often there is no variant where function take valist instead of ...
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
if(values.length==1) someCfunction(345,values[0].toString());
else if(values.length==2)
someCfunction(543,values[0].toString(),values[1].toString());
//etc...
}

There must be a better way to do this...


 
 
 Redeclare someCfunction as:
 
 void someCfunction(int[] a ...)
 
 


extern(C) void someCfunction(int[] a...)
{
	printf("as %d %d\0",a);
}

int main(char[][] argv)
{
	int[] a;
	a~=5;a~=6;
	someCfunction(a);
	return 1;
}

outputs "as 2 9243472"
Dec 02 2005
parent reply pragma <pragma_member pathlink.com> writes:
In article <dmpvro$2b3f$1 digitaldaemon.com>, bobef says...

Walter Bright wrote:

 "bobef" <bobef lessequal.com> wrote in message
 news:dmfcgr$2hpa$1 digitaldaemon.com...
 

Is there some way to pass something like array to variadic function. I
mean often there is no variant where function take valist instead of ...
and when you need to wrap this function what do you do? Write many ifs?
I will illustrate my question with example

void someCfunction(int a,...)
{
... do stuff here
}


void dmdscript_for_example_function(/*all_the_stuff*/,Value[] values)
{
if(values.length==1) someCfunction(345,values[0].toString());
else if(values.length==2)
someCfunction(543,values[0].toString(),values[1].toString());
//etc...
}

There must be a better way to do this...


 
 
 Redeclare someCfunction as:
 
 void someCfunction(int[] a ...)
 
 


extern(C) void someCfunction(int[] a...)
{
	printf("as %d %d\0",a);
}

int main(char[][] argv)
{
	int[] a;
	a~=5;a~=6;
	someCfunction(a);
	return 1;
}

outputs "as 2 9243472"


Try this:


extern(C) void someCfunction(int[] a...)
{
	writefln("as %s",a);
}


- EricAnderton at yahoo
Dec 02 2005
parent bobef <bobef lessequal.com> writes:
pragma wrote:

outputs "as 2 9243472"


 
 
 Try this:
 
 

extern(C) void someCfunction(int[] a...)
{
	writefln("as %s",a);
}


 
 
 - EricAnderton at yahoo


I got confused....... This is the real code I am asking the question 
for. There is no xchat_emit_writefln... And xchat_emit_print is what I 
meant with someCfunction...


//this is part of struct actually
extern(C) int (*xchat_emit_print) (xchat_plugin *ph,char *event_name, ...);

void* g_xchat_emit_print(Dobject pthis,CallContext* cc,Dobject 
othis,Value* ret,Value[] arglist)
{
	//todo: the whole arglist should be passed to the variadic function
	Value *v=getErrorReturn(arglist,1,"xchat_emit_print");
	if(!v)
	{
		if(arglist.length==1) 
this_ph.xchat_emit_print(this_ph,toStringz(arglist[0].toString()));
		else if(arglist.length==2) 
this_ph.xchat_emit_print(this_ph,toStringz(arglist[0].toString()),toStringz(arglist[1].toString()));
	//............
}
Dec 03 2005