From: Lionel Thiry <lthiry@...>
Date: 2004-10-15T07:35:30+09:00
Subject: Re: [nuby] shell-like substitution in a string

Ara.T.Howard@noaa.gov a �crit :

> On Thu, 14 Oct 2004, Lionel Thiry wrote:
> 
>> Hi!
>>
>> I'd like to make some kind of substitution like in a shell, i.e. having:
>> "${tool} -o ${target} -L${libpath} -l${lib} ${source}"
>>
>> with an env like this:
>> env = {
>> "tool" => "gcc",
>> "target" => "hello.exe",
>> "libpath" => "/usr/lib",
>> "lib" => "somelib",
>> "source" => "hello.c"
>> }
>>
>> it should give:
>> "gcc -o hello.exe -L/usr/lib -lsomelib hello.c"
>>
>>
>> It is easy until I want to manage caracter escapement like
>> "${var\\}weird}" which should give env["var}weird"],  "\\${var}" which
>> should give the simple string "${var}" and "\\\\${var}" which should be
>> equivalent to "\\" + env["var"].
> 
> 
> i don't think you need to worry about that since 'var}weird' is not a valid
> shell identifier - at least i can't seem to create a var by that name in 
> the
> shell...
Pertinent remark, noted.

> 
>> Any idea of how I could manage that?
> 
> 
> you can get bash's exact parameter expansion like this:
> 
>   jib:~ > cat a.rb
>   require 'session'
I'm working on win2k with on-click installer ruby v1.8.1-13 and 
unfortunately, there is no session file that can be required.

Lionel Thiry