• Andrei Alexandrescu (7/7) Jan 22 2011 OK, so we have replace(haystack, needle, nail) which replaces _all_
• Andrej Mitrovic (3/3) Jan 22 2011 What if you want to replace a _count_ number of occurrences of needle
• Andrei Alexandrescu (5/8) Jan 22 2011 A specific count is rare but can be added as a defaulted parameter. The
• Justin Johansson (10/17) Jan 22 2011 If you articulate this question to yourself over and over until you
• Andrei Alexandrescu (3/23) Jan 22 2011 Now I am feeling lost indeed :o).
• Torarin (3/10) Jan 22 2011 It sounds like the current replace should be named replaceAll.
• so (4/6) Jan 22 2011 replaceAll
• Andrei Alexandrescu (5/19) Jan 22 2011 That's what I'm fearing - changing current replace to replaceAll and
• Daniel Gibson (6/28) Jan 22 2011 IMHO replace (without eny suffix) sounds like it replaces every occurenc...
• bearophile (4/7) Jan 22 2011 OK.
• Paul D. Anderson (3/35) Jan 22 2011 This was my first thought, too.
• Torarin (5/9) Jan 22 2011 Yeah, I see that problem. I'm just so used to "replace first" being
• Adam D. Ruppe (18/19) Jan 22 2011 That would break lots of existing code, and it doesn't seem to
• spir (16/22) Jan 22 2011 Apart voting for replaceFirst:
• Andrej Mitrovic (3/5) Jan 22 2011 Isn't Andrei talking about std.algorithm.replace, which should work
• Nick Sabalausky (5/11) Jan 22 2011 replaceFirst

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

OK, so we have replace(haystack, needle, nail) which replaces _all_ 
occurrences of needle in haystack with nail. How would you call a 
function that replaces only the _first_ occurrence of needle with nail?

Must be a distinct function, not a runtime parameter to the existing 
function. This is because the function that replaces only one occurrence 
only requires nail to be an input range.


Andrei

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

What if you want to replace a _count_ number of occurrences of needle
in haystack with nail? That's what Python's replace does, although I
think that only works for strings in Python.

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 1/22/11 10:47 AM, Andrej Mitrovic wrote:
 What if you want to replace a _count_ number of occurrences of needle
 in haystack with nail? That's what Python's replace does, although I
 think that only works for strings in Python.

A specific count is rare but can be added as a defaulted parameter. The 
only problem is that one is special because it accepts a weaker range as 
replacement.

Andrei

Justin Johansson <jj nospam.com> writes:

On 23/01/11 03:27, Andrei Alexandrescu wrote:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a
 function that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

If you articulate this question to yourself over and over until you 
understand the *salient* problem (i.e. the real problem that sticks out) 
you will answer your own question and then have no need to resort to 
newsgroup answers.

If you are feeling lost, a good tactic to solve your problem is to think 
about function signatures in all their D glory not forgetting, of 
course, about D's innovative transitive xxx (const/immutable) constructs 
to include in the specification of your function(s).

Justin

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 1/22/11 11:03 AM, Justin Johansson wrote:
 On 23/01/11 03:27, Andrei Alexandrescu wrote:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a
 function that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

 If you articulate this question to yourself over and over until you
 understand the *salient* problem (i.e. the real problem that sticks out)
 you will answer your own question and then have no need to resort to
 newsgroup answers.

 If you are feeling lost, a good tactic to solve your problem is to think
 about function signatures in all their D glory not forgetting, of
 course, about D's innovative transitive xxx (const/immutable) constructs
 to include in the specification of your function(s).

 Justin

Now I am feeling lost indeed :o).

Andrei

Torarin <torarind gmail.com> writes:

2011/1/22 Andrei Alexandrescu <SeeWebsiteForEmail erdani.org>:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a function
 that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

It sounds like the current replace should be named replaceAll.

Torarin

so <so so.do> writes:

 It sounds like the current replace should be named replaceAll.

 Torarin

replaceAll
replaceN
replaceFirst
replaceLast

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 1/22/11 11:38 AM, Torarin wrote:
 2011/1/22 Andrei Alexandrescu<SeeWebsiteForEmail erdani.org>:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a function
 that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

 It sounds like the current replace should be named replaceAll.

 Torarin

That's what I'm fearing - changing current replace to replaceAll and 
adding replace with the meaning of replaceFirst would silently change 
the semantics of existing code.

Andrei

Daniel Gibson <metalcaedes gmail.com> writes:

Am 22.01.2011 18:46, schrieb Andrei Alexandrescu:
 On 1/22/11 11:38 AM, Torarin wrote:
 2011/1/22 Andrei Alexandrescu<SeeWebsiteForEmail erdani.org>:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a
 function
 that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

 It sounds like the current replace should be named replaceAll.

 Torarin

 That's what I'm fearing - changing current replace to replaceAll and
 adding replace with the meaning of replaceFirst would silently change
 the semantics of existing code.

 Andrei

IMHO replace (without eny suffix) sounds like it replaces every occurence.
So just add replaceFirst for a function that replaces only the first 
occurence :)

Cheers,
- Daniel

bearophile <bearophileHUGS lycos.com> writes:

Daniel Gibson:

 IMHO replace (without eny suffix) sounds like it replaces every occurence.
 So just add replaceFirst for a function that replaces only the first 
 occurence :)

OK.

Bye,
bearophile

Paul D. Anderson <paul.removethis.d.anderson comcast.andthis.net> writes:

Daniel Gibson Wrote:

 Am 22.01.2011 18:46, schrieb Andrei Alexandrescu:
 On 1/22/11 11:38 AM, Torarin wrote:
 2011/1/22 Andrei Alexandrescu<SeeWebsiteForEmail erdani.org>:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a
 function
 that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.


 Andrei

 It sounds like the current replace should be named replaceAll.

 Torarin

 That's what I'm fearing - changing current replace to replaceAll and
 adding replace with the meaning of replaceFirst would silently change
 the semantics of existing code.

 Andrei

 
 IMHO replace (without eny suffix) sounds like it replaces every occurence.
 So just add replaceFirst for a function that replaces only the first 
 occurence :)
 
 Cheers,
 - Daniel

This was my first thought, too.

Paul

Torarin <torarind gmail.com> writes:

2011/1/22 Andrei Alexandrescu <SeeWebsiteForEmail erdani.org>:

 That's what I'm fearing - changing current replace to replaceAll and adding
 replace with the meaning of replaceFirst would silently change the semantics
 of existing code.

 Andrei

Yeah, I see that problem. I'm just so used to "replace first" being
the default in text editors, and then you have a "replace all" button
if you want to replace everything. That also seems to be Walter's
reasoning in std.typetuple.

Adam D. Ruppe <destructionator gmail.com> writes:

Torarin wrote:
 It sounds like the current replace should be named replaceAll.

That would break lots of existing code, and it doesn't seem to
fit.

If replacing only the first element means it can take a special
range, whereas all other n is is the same, it seems obvious
that replaceFirst be the special function (that's what I'd call
it too) and normal replace be either:

a) Kept exactly as it is

b) Add a runtime parameter:

string replace(string item, string replaceWhat, string replaceWith, int howMany
=
int.max);

So it stays the same as it is now by default, but can cover
any number of items in the same way.



If n == infinity was a special case for algorithm or input,
it'd make sense to give it a special name (though still big
points against it because of inertia). But it isn't. n==1 is
special, but n != 1 is always the same.

So I'd say go replaceFirst.

spir <denis.spir gmail.com> writes:

On 01/22/2011 05:27 PM, Andrei Alexandrescu wrote:
 OK, so we have replace(haystack, needle, nail) which replaces _all_
 occurrences of needle in haystack with nail. How would you call a
 function that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing
 function. This is because the function that replaces only one occurrence
 only requires nail to be an input range.

Apart voting for replaceFirst:

Python doc:
string.replace(str, old, new[, maxreplace])¶
     Return a copy of string str with all occurrences of substring old 
replaced by new. If the optional argument maxreplace is given, the first 
maxreplace occurrences are replaced.

In years and years of string processing, I have used maxreplace once, I 
guess, and the value was not 1. Does something like replace first belong 
to stdlib? Even more if it needs be so special. When needed, isnt'it 
easy to write in two lines using find's result? Also, what is the 
correct behaviour when not found (what is the one true way)?


Denis
_________________
vita es estrany
spir.wikidot.com

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

On 1/22/11, spir <denis.spir gmail.com> wrote:
 In years and years of string processing, I have used maxreplace once, I
 guess, and the value was not 1.

Isn't Andrei talking about std.algorithm.replace, which should work
with any range and not just strings?

"Nick Sabalausky" <a a.a> writes:

"Andrei Alexandrescu" <SeeWebsiteForEmail erdani.org> wrote in message 
news:ihf0kc$2fqj$1 digitalmars.com...
 OK, so we have replace(haystack, needle, nail) which replaces _all_ 
 occurrences of needle in haystack with nail. How would you call a function 
 that replaces only the _first_ occurrence of needle with nail?

 Must be a distinct function, not a runtime parameter to the existing 
 function. This is because the function that replaces only one occurrence 
 only requires nail to be an input range.

replaceFirst

As for the question of renaming "replace" to "replaceAll", I'd lean more 
towards "replace", but I honestly don't actually care either way.