[ruby-core:65928] [CommonRuby - Feature #8848] Syntax for binary strings

Issue #8848 has been updated by Eric Wong.


 [e-mail] wrote:
 > One reason for this efficiency. String#b creates a duplicate object,
 > which is not at all necessary for the frequent use case of String
 > literals.
 
 Avoiding one allocation is easy to add to [Feature #10423]
 (which avoids string literal allocations for many methods)
 
 > Another reason is encoding validity. To be able to e.g. create a
 > "\xFF" binary string, with String#b in an UTF-8 source context, it is
 > necessary to allow "\xFF" (temporarily at least) as an (actually
 > invalid) UTF-8 string. This may be difficult for some implementations,
 > and isn't desirable in general.
 
 We can even go farther than #10423 and move the evaluation of
 "string literal".{b,encode,force_encoding} to compile time.
 
 The downside is compatibility with people who wish to override one of
 those methods, but doubt anybody overrides those...
 There's no new (and strange looking, IMHO) syntax to learn,
 it looks like a normal method call, and the optimization would be
 usable with existing code.

----------------------------------------
Feature #8848: Syntax for binary strings
https://bugs.ruby-lang.org/issues/8848#change-49665

* Author: Martin D端rst
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
----------------------------------------
In commit 37486, Yui (Naruse) added a String#b method as proposed in http://bugs.ruby-lang.org/issues/6767.

String#b was added to allow easy generation of binary strings; this became necessary in particular after the source file encoding was changed to UTF-8.

However, as also recognized in http://bugs.ruby-lang.org/issues/6767, in the long term (ideally starting with Ruby 2.1) it would be better to make binary strings available as part of Ruby syntax.

One reason for this efficiency. String#b creates a duplicate object, which is not at all necessary for the frequent use case of String literals.

Another reason is encoding validity. To be able to e.g. create a "\xFF" binary string, with String#b in an UTF-8 source context, it is necessary to allow "\xFF" (temporarily at least) as an (actually invalid) UTF-8 string. This may be difficult for some implementations, and isn't desirable in general.

Regarding syntax, there are mainly two solutions:

1) a '%b' prefix
2) a 'b' suffix

The preferable syntax depends on the overall future approach of Ruby to String literal suffixes (see https://bugs.ruby-lang.org/issues/8579).



-- 
https://bugs.ruby-lang.org/