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digitalmars.D.learn - BitArray - incomplete implementation?

reply "Laeeth Isharc" <laeethnospam nospam.laeeth.com> writes:
Hi.

Should the following code work?

import std.bitmanip;
import std.stdio;
import std.array;
import std.range:chain;

void test()
{
	int[] a=[1,2,3,4,5];
	int[] b=[5,4,3,2,1];
	int[] c = chain(a,b).array; // chain two arrays of int
	writefln("%s",c);
}

void test2()
{
	BitArray a;
	a.init([1,0,1,0]);
	BitArray b;
	b.init([0,1,0,1]);
	BitArray[] d;
	d~=a;
	d~=b;
	BitArray[] c=chain([a],[b]).array; // cannot chain two bitarrays
	BitArray[] e=chain(d,d).array; // cannot chain two arrays of 
bitarrays
	writefln("%s",c);
}

int main(string[] args)
{
	test();
	test2();
	return 1;
}

bitmanip.d(23): Error: template std.range.chain cannot deduce 
function from argument types !()(BitArray, BitArray), candidates 
are:
/usr/include/dmd/phobos/std/range.d(2493):        
std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
!is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
Ranges))) == void))
bitmanip.d(24): Error: template std.range.chain cannot deduce 
function from argument types !()(BitArray[], BitArray[]), 
candidates are:
/usr/include/dmd/phobos/std/range.d(2493):        
std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
!is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
Ranges))) == void))
bitmanip.d(24): Error: declaration bitmanip.test2.c is already 
defined
bitmanip.d(25): Error: template std.range.chain cannot deduce 
function from argument types !()(BitArray[], BitArray[]), 
candidates are:
/usr/include/dmd/phobos/std/range.d(2493):        
std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
!is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
Ranges))) == void))

I cannot seem to concatenate - directly, or using chain - two 
bitarrays, or two arrays of bitarrays.
Jan 23 2015
next sibling parent "Laeeth Isharc" <laeethnospam nospam.laeeth.com> writes:
To avoid confusion, the below is the code that fits the error 
message:

import std.bitmanip;
import std.stdio;
import std.array;
import std.range:chain;

void test()
{
	int[] a=[1,2,3,4,5];
	int[] b=[5,4,3,2,1];
	int[] c = chain(a,b).array; // chain two arrays of int
	writefln("%s",c);
}

void test2()
{
	BitArray a;
	a.init([1,0,1,0]);
	BitArray b;
	b.init([0,1,0,1]);
	BitArray[] d;
	d~=a;
	d~=b;
	BitArray[] c=chain(a,b).array; // cannot chain two bitarrays
	BitArray[] c=chain([a],[b]).array; // cannot chain two bitarrays
	BitArray[] e=chain(d,d).array; // cannot chain two arrays of 
bitarrays
	writefln("%s",c);
}

int main(string[] args)
{
	test();
	test2();
	return 1;
}
Jan 23 2015
prev sibling parent reply "anony" <anonymous mail.invalid> writes:
On Saturday, 24 January 2015 at 00:13:34 UTC, Laeeth Isharc wrote:

 Hi.

 Should the following code work?


Yes, that error is caused by a bug of 
BitArray(https://issues.dlang.org/show_bug.cgi?id=13806). Having 
"init" function broke template constraints of "chain"(and must 
break dozen of other templates).

pragma(msg, ElementType!(BitArray[])) // prints 'pure nothrow 
void(bool[] ba)' - ElementType uses "init" property to determine 
types.


 import std.bitmanip;
 import std.stdio;
 import std.array;
 import std.range:chain;

 void test()
 {
 	int[] a=[1,2,3,4,5];
 	int[] b=[5,4,3,2,1];
 	int[] c = chain(a,b).array; // chain two arrays of int
 	writefln("%s",c);
 }

 void test2()
 {
 	BitArray a;
 	a.init([1,0,1,0]);
 	BitArray b;
 	b.init([0,1,0,1]);
 	BitArray[] d;
 	d~=a;
 	d~=b;
 	BitArray[] c=chain([a],[b]).array; // cannot chain two 
 bitarrays
 	BitArray[] e=chain(d,d).array; // cannot chain two arrays of 
 bitarrays
 	writefln("%s",c);
 }

 int main(string[] args)
 {
 	test();
 	test2();
 	return 1;
 }

 bitmanip.d(23): Error: template std.range.chain cannot deduce 
 function from argument types !()(BitArray, BitArray), 
 candidates are:
 /usr/include/dmd/phobos/std/range.d(2493):        
 std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
 allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
 !is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
 Ranges))) == void))
 bitmanip.d(24): Error: template std.range.chain cannot deduce 
 function from argument types !()(BitArray[], BitArray[]), 
 candidates are:
 /usr/include/dmd/phobos/std/range.d(2493):        
 std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
 allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
 !is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
 Ranges))) == void))
 bitmanip.d(24): Error: declaration bitmanip.test2.c is already 
 defined
 bitmanip.d(25): Error: template std.range.chain cannot deduce 
 function from argument types !()(BitArray[], BitArray[]), 
 candidates are:
 /usr/include/dmd/phobos/std/range.d(2493):        
 std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
 allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
 !is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
 Ranges))) == void))

 I cannot seem to concatenate - directly, or using chain - two 
 bitarrays, or two arrays of bitarrays.
Jan 23 2015
parent "Laeeth Isharc" <laeethnospam nospam.laeeth.com> writes:
 Yes, that error is caused by a bug of 
 BitArray(https://issues.dlang.org/show_bug.cgi?id=13806). 
 Having "init" function broke template constraints of 
 "chain"(and must break dozen of other templates).

 pragma(msg, ElementType!(BitArray[])) // prints 'pure nothrow 
 void(bool[] ba)' - ElementType uses "init" property to 
 determine types.



Thanks for this.  If I recompile phobos with the pull request 
(having edited out the init property entirely) then the code 
mostly works.

However, I still can't use join, joiner, or chain on two 
BitArrays.  Eg
auto x=joiner(a,b).array;

I can chain two arrays of BitArrays, but not join or joiner them.

If this is what ought to happen, why?
Jan 23 2015