On 2010-02-20 15:48:10 -0500, Andrei Alexandrescu
<seewebsiteforem...@erdani.org> said:
To focus the discussion about naming conventions, let's discuss one
particular aspect. Right now we have in std.algorithm:
=======================
/**
If the range $(D doesThisStart) starts with $(I any) of the $(D
withOneOfThese) ranges or elements, returns 1 if it starts with $(D
withOneOfThese[0]), 2 if it starts with $(D withOneOfThese[1]), and so
on. If no match, returns 0.
Example:
----
assert(startsWith("abc", ""));
assert(startsWith("abc", "a"));
assert(!startsWith("abc", "b"));
assert(startsWith("abc", 'a', "b") == 1);
assert(startsWith("abc", "b", "a") == 2);
assert(startsWith("abc", "a", "a") == 1);
assert(startsWith("abc", "x", "a", "b") == 2);
assert(startsWith("abc", "x", "aa", "ab") == 3);
assert(startsWith("abc", "x", "aaa", "sab") == 0);
assert(startsWith("abc", "x", "aaa", 'a', "sab") == 3);
----
*/
uint startsWith(alias pred = "a == b", Range, Ranges...)
(Range doesThisStart, Ranges withOneOfThese);
=======================
I also defined recently:
=======================
/**
If $(D startsWith(r1, r2)), consume the corresponding elements off $(D
r1) and return $(D true). Otherwise, leave $(D r1) unchanged and
return $(D false).
*/
bool startsWithConsume(R1, R2)(ref R1 r1, R2 r2);
=======================
There are a few other functions like that: one version takes a range by
value, the other takes it by reference and alters it.
The question is, what is a good naming convention for expressing that?
Other examples: findConsume, consumeFind.
Instead of "startsWithConsume" you could use "consumePrefix" which
sounds better. You could change "startsWith" to "hasPrefix" too to keep
things consistent, even though "startsWith" isn't a bad name in itself.
The small string parsing module I made has "consumeUntil" that consumes
until a predicate tells it to stop.
In fact, all my consuming primitives advancing over the string and
returning a boolean starts with "consume", this makes their role very
clear. I also have a "read" family of function that uses consumers as
predicate to extract consumed strings return them. So I can write fun
things like this:
alias isChar!(' ') isSpace;
alias isNotChar!(' ') isNotSpace;
alias consumeOneWhile!(isNotSpace) consumeWord;
alias consumeOneWhile!(isSpace) consumeSpaces;
alias read!(consumeWord) readWord;
string a = "hello world of fear ! ";
string[] result = readSplit!(readWord, consumeSpaces)(a);
assert(result == ["hello", "world", "of", "fear", "!"]);
--
Michel Fortin
michel.for...@michelf.com
http://michelf.com/
