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digitalmars.D - std.string import cleanup: how to fix regression?

reply "H. S. Teoh via Digitalmars-d" <digitalmars-d puremagic.com> writes:
Recently, Ilya has been helping to clean up import dependencies between
Phobos module. In the course of cleaning up std.string, a few public
imports were removed because they were not referenced by the module
itself. However, this caused a regression:

https://issues.dlang.org/show_bug.cgi?id=13717

The code that got removed was:

------
//Remove when repeat is finally removed. They're only here as part of the
//deprecation of these functions in std.string.
public import std.algorithm : startsWith, endsWith, cmp, count;
public import std.array : join, split;
------


From the comment, it seems clear that the intent is to move these


functions out of std.string into std.algorithm and std.array. However,
there is currently no way to deprecate public imports, so we can't get
rid of this dependency without breaking user code (one of my projects
already doesn't compile because of this).

What should we do? Anybody has a good idea for getting rid of the
gratuitous dependency on std.algorithm / std.array without breaking user
code with no warning?


T

-- 
EMACS = Extremely Massive And Cumbersome System
Nov 12 2014
next sibling parent "Ilya Yaroshenko" <ilyayaroshenko gmail.com> writes:
One solution is new `extern import std.array : split;` syntax. 
Like `public` but do *not* visible for module itself.
If user will use selective imports with std.string, than there 
compiler can deduce dependencies without full imports.

Furthermore we can deprecate it lately with  `deprecated extern 
import std.array : split;`


 What should we do? Anybody has a good idea for getting rid of 
 the
 gratuitous dependency on std.algorithm / std.array without 
 breaking user
 code with no warning?


 T
Nov 12 2014
prev sibling next sibling parent reply "Dicebot" <public dicebot.lv> writes:
Will this work?

static import std.string;
deprecated public alias split = std.string.split;
Nov 12 2014
parent reply "Daniel Kozak" <kozzi11 gmail.com> writes:
On Wednesday, 12 November 2014 at 17:52:27 UTC, Dicebot wrote:

 Will this work?

 static import std.string;
 deprecated public alias split = std.string.split;


Yes, but not for all cases. If I have code where I import 
std.string and use std.algoritm.startsWith(...), then it would 
not work
Nov 13 2014
parent "Daniel Kozak" <kozzi11 gmail.com> writes:
On Thursday, 13 November 2014 at 08:18:22 UTC, Daniel Kozak wrote:

 On Wednesday, 12 November 2014 at 17:52:27 UTC, Dicebot wrote:

 Will this work?

 static import std.string;
 deprecated public alias split = std.string.split;


 Yes, but not for all cases. If I have code where I import 
 std.string and use std.algoritm.startsWith(...), then it would 
 not work


But this can be solved by something like this:

deprecated {
     static struct std {
         static struct algorithm {
             static import std.algorithm;
             alias startsWith = std.algorithm.startsWith;
         }
     }
}

However than you can`t use global imports
Nov 13 2014
prev sibling parent reply "Daniel Kozak" <kozzi11 gmail.com> writes:
On Wednesday, 12 November 2014 at 17:27:18 UTC, H. S. Teoh via 
Digitalmars-d wrote:

 Recently, Ilya has been helping to clean up import dependencies 
 between
 Phobos module. In the course of cleaning up std.string, a few 
 public
 imports were removed because they were not referenced by the 
 module
 itself. However, this caused a regression:

 https://issues.dlang.org/show_bug.cgi?id=13717

 The code that got removed was:

 ------
 //Remove when repeat is finally removed. They're only here as 
 part of the
 //deprecation of these functions in std.string.
 public import std.algorithm : startsWith, endsWith, cmp, count;
 public import std.array : join, split;
 ------


From the comment, it seems clear that the intent is to move 
these


 functions out of std.string into std.algorithm and std.array. 
 However,
 there is currently no way to deprecate public imports, so we 
 can't get
 rid of this dependency without breaking user code (one of my 
 projects
 already doesn't compile because of this).

 What should we do? Anybody has a good idea for getting rid of 
 the
 gratuitous dependency on std.algorithm / std.array without 
 breaking user
 code with no warning?


 T


What about:

static import std.algorithm : startsWith, endsWith, cmp, count;
static import std.array : join, split;

deprecated {
     alias startsWith = std.algorithm.startsWith;
     ...
}
Nov 13 2014
parent reply "Ilya Yaroshenko" <ilyayaroshenko gmail.com> writes:
alias can not be deprecated :-(

 What about:

 static import std.algorithm : startsWith, endsWith, cmp, count;
 static import std.array : join, split;

 deprecated {
     alias startsWith = std.algorithm.startsWith;
     ...
 }
Nov 13 2014
next sibling parent "H. S. Teoh via Digitalmars-d" <digitalmars-d puremagic.com> writes:
On Thu, Nov 13, 2014 at 07:27:57PM +0000, Ilya Yaroshenko via Digitalmars-d
wrote:

 alias can not be deprecated :-(

What about:

static import std.algorithm : startsWith, endsWith, cmp, count;
static import std.array : join, split;

deprecated {
    alias startsWith = std.algorithm.startsWith;
    ...
}




Maybe we should file an enhancement request to make alias deprecatable.
I know recently someone asked for the 'module' declaration to be
deprecatable, and it was implemented. Maybe it's time to extend that to
aliases too. :-)


T

-- 
There's light at the end of the tunnel. It's the oncoming train.
Nov 13 2014
prev sibling parent "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:
On Thursday, 13 November 2014 at 19:27:59 UTC, Ilya Yaroshenko 
wrote:

 alias can not be deprecated :-(


It can. But evidently, static import cannot be selective:

aa.d:
     static import std.algorithm;// : startsWith, endsWith, cmp, 
count;
     static import std.array;// : join, split;

     deprecated {
         alias startsWith = std.algorithm.startsWith;
     }

bb.d:
     import aa;
     bool test() {
         return "".startsWith("");
     }


bb.d(2): Deprecation: alias aa.startsWith is deprecated

Remove ";//" to enable the selective imports, and we get errors:
aa.d(1): Error: static import std cannot have an import bind list
aa.d(1): Error: static import __anonymous cannot have an import 
bind list
aa.d(1): Error: static import __anonymous cannot have an import 
bind list
aa.d(1): Error: static import __anonymous cannot have an import 
bind list
aa.d(2): Error: static import std cannot have an import bind list
aa.d(2): Error: static import __anonymous cannot have an import 
bind list

This seems like an arbitrary restriction. [1] states that it is 
disallowed (under the heading "Selective Imports"), but gives no 
justification. It's probably because of the implementation.

Anyway, the imports can be pulled into the `deprecated` block to 
make the intention clear:

     deprecated {
         static import std.algorithm;
         static import std.array;

         alias startsWith = std.algorithm.startsWith;
     }


[1] http://dlang.org/module
Nov 13 2014