2012年4月23日21:36 Denis Shelomovskij <verylonglogin.reg at gmail.com>:
> I've never used new excellent range formatting syntax by Kenji Hara until
> now. And I've met with difficulties, because "%(%(%c%), %)" is the most
> common format for string array for me and it neither obvious nor elegant. It
> occurs that "%c" disables character escaping. What the hell? Why? Not
> obvious at all.
>
> So I think it will be good to add 'Escaping' part after 'Precision' in
> format specifications:
>
> Escaping:
> empty
> !-
> !+
> !'
> !"
> !?'
> !?"
> !?!
>
> Escaping affect formatting depending on the specifier as follows.
>
> Escaping Semantics
> !- disable escaping, for a range it also disables [,]
> !+ enable escaping using single quotes for chars and double quotes for
> strings
> !' enable escaping using single quotes
> !" enable escaping using double quotes
> !?' like !' but without adding the quotes and [,] for a range
> !?" like !" but without adding the quotes and [,] for a range
> !?! enable escaping, both single and double quotes will be escaped
> without adding any quotes and [,] for a range
>
> Escaping is enabled by default only for associative arrays, ranges (not
> strings), user-defined types, and all its sub-elements.
>
> I'd like to remove "%c"'s ability to magically disable escaping and it looks
> possible until it is documented.
>
> Look at the example:
> ---
> import std.stdio;
>
> void main() {
> writeln(" char");
> char c = '\'';
> writefln("unescaped: %s." , c );
> writefln(`escaped+': %(%).`, [ c ]); // proposal: %!+s or %!'s
> writefln(`escaped+": %(%).`, [[c]]); // proposal: %!"s
> writeln (` escaped: \t.`); // proposal: %!?'s
> writeln();
> writeln(" string");
> string s = "a\tb";
> writefln("unescaped: %s." , s );
> writefln(`escaped+": %(%).`, [s]); // proposal: %!+s or %!"s
> writeln (` escaped: a\tb.`); // proposal: %!?"s
> writeln();
> writeln(" strings");
> string[] ss = ["a\tb", "cd"];
> writefln("unescaped: %(%(%c%)%).", ss); // proposal: %!-s
> writefln(`escaped+": %(%).` , ss);
> writeln (` escaped: a\tbcd.` , ss); // proposal: %!?"s
> }
> ---
>
> If it will be accepted, I can volunteer to try to implement it. If not,
> escaping should be at least documented (and do not forget about "%c"'s
> magic!).
>
> Any thoughts?
Please give us use cases.
I cannot imagine why you want to change/remove quotations but keep
escaped contents.
> P.S.
> If it has already been discussed, please give me a link.
As far as I know, there is not yet discussions.
Kenji Hara