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digitalmars.D.learn - std.algorithm.splitter improovement?

reply "seany" <seany uni-bonn.de> writes:
the std.algorithm.splitter returns a blank or null (eg a null 
string "") between two consecuting delimeters.

for example, splitting "hello  world" (two spaces between words) 
will return ["hello" , "", "world"]

is there an improoved version of it, which wont return such a 
blank/null when multiple delimeters are found consecutively? (i 
tried to search the tango for d2, but i was not successful, 
should there be one like this already, it must have escaped my 
sight)
Dec 14 2013
next sibling parent "Peter Alexander" <peter.alexander.au gmail.com> writes:
On Saturday, 14 December 2013 at 16:00:06 UTC, seany wrote:

 the std.algorithm.splitter returns a blank or null (eg a null 
 string "") between two consecuting delimeters.

 for example, splitting "hello  world" (two spaces between 
 words) will return ["hello" , "", "world"]

 is there an improoved version of it, which wont return such a 
 blank/null when multiple delimeters are found consecutively? (i 
 tried to search the tango for d2, but i was not successful, 
 should there be one like this already, it must have escaped my 
 sight)


Just filter out the empty ranges:

r.splitter().filter!(x => !x.empty)
Dec 14 2013
prev sibling parent reply "bearophile" <bearophileHUGS lycos.com> writes:
seany:


 for example, splitting "hello  world" (two spaces between 
 words) will return ["hello" , "", "world"]


It's a bug.

Bye,
bearophile
Dec 14 2013
parent reply Marco Leise <Marco.Leise gmx.de> writes:
Am Sat, 14 Dec 2013 17:41:22 +0100
schrieb "bearophile" <bearophileHUGS lycos.com>:


 seany:
 

 for example, splitting "hello  world" (two spaces between 
 words) will return ["hello" , "", "world"]


 
 It's a bug.
 
 Bye,
 bearophile


Not at all, the documentation explicitly states:

  assert(equal(splitter("hello  world", ' '), [ "hello", "", "world" ]));

-- 
Marco
Dec 14 2013
parent reply "bearophile" <bearophileHUGS lycos.com> writes:
Marco Leise:


 Not at all, the documentation explicitly states:

   assert(equal(splitter("hello  world", ' '), [ "hello", "", 
 "world" ]));


I didn't see the ' ' in the OP code, sorry.

A test:


void main() {
     import std.stdio, std.string, std.algorithm;
     auto s = "hello  world";
     s.split().writeln;
     std.array.splitter(s).writeln;
     s.splitter(' ').writeln;
}


The output seems OK:

["hello", "world"]
["hello", "world"]
["hello", "", "world"]

Bye,
bearophile
Dec 14 2013
next sibling parent Dmitry Olshansky <dmitry.olsh gmail.com> writes:
14-Dec-2013 21:20, bearophile пишет:

 Marco Leise:


 Not at all, the documentation explicitly states:

   assert(equal(splitter("hello  world", ' '), [ "hello", "", "world" ]));


 I didn't see the ' ' in the OP code, sorry.

 A test:


 void main() {
      import std.stdio, std.string, std.algorithm;
      auto s = "hello  world";
      s.split().writeln;
      std.array.splitter(s).writeln;
      s.splitter(' ').writeln;
 }


 The output seems OK:


Yup, there are 2 splitters - one that uses explicit separator and one 
that uses predicate. AFAIK the default predicate is std.uni.isWhite.


 ["hello", "world"]
 ["hello", "world"]
 ["hello", "", "world"]

 Bye,
 bearophile



-- 
Dmitry Olshansky
Dec 14 2013
prev sibling parent reply Marco Leise <Marco.Leise gmx.de> writes:
Am Sat, 14 Dec 2013 18:20:13 +0100
schrieb "bearophile" <bearophileHUGS lycos.com>:


 Marco Leise:
 

 Not at all, the documentation explicitly states:

   assert(equal(splitter("hello  world", ' '), [ "hello", "", 
 "world" ]));


 
 I didn't see the ' ' in the OP code, sorry.
 
 A test:
 
 
 void main() {
      import std.stdio, std.string, std.algorithm;
      auto s = "hello  world";
      s.split().writeln;
      std.array.splitter(s).writeln;
      s.splitter(' ').writeln;
 }
 
 
 The output seems OK:
 
 ["hello", "world"]
 ["hello", "world"]
 ["hello", "", "world"]
 
 Bye,
 bearophile


Somehow I cannot say this makes me happy. I totally thought
there was only one splitter and it has to be used with a
delimiter. You are right that the OP didn't say which version
he used. The result made it clear in the end. So the solution
to this is "use the other splitter".

-- 
Marco
Dec 14 2013
parent "seany" <seany uni-bonn.de> writes:
On Sunday, 15 December 2013 at 01:25:39 UTC, Marco Leise wrote:

 Am Sat, 14 Dec 2013 18:20:13 +0100
 schrieb "bearophile" <bearophileHUGS lycos.com>:


 Marco Leise:
 

 Not at all, the documentation explicitly states:

   assert(equal(splitter("hello  world", ' '), [ "hello", "", 
 "world" ]));


 
 I didn't see the ' ' in the OP code, sorry.
 
 A test:
 
 
 void main() {
      import std.stdio, std.string, std.algorithm;
      auto s = "hello  world";
      s.split().writeln;
      std.array.splitter(s).writeln;
      s.splitter(' ').writeln;
 }
 
 
 The output seems OK:
 
 ["hello", "world"]
 ["hello", "world"]
 ["hello", "", "world"]
 
 Bye,
 bearophile


 Somehow I cannot say this makes me happy. I totally thought
 there was only one splitter and it has to be used with a
 delimiter. You are right that the OP didn't say which version
 he used. The result made it clear in the end. So the solution
 to this is "use the other splitter".


I was using, as I said, std.algorithm.splitter, and I did not 
know that it could be called without a delimeter. i always called 
it like

std.algorithm.splitter("hello  world", ' '); //two spaces in array

And that is giving me one empty element.
Dec 15 2013