From: Robert Klemme <shortcutter@...>
Date: 2009-05-25T20:44:44+09:00
Subject: Re: String concatenation in Ruby

2009/5/25 Bertram Scharpf <lists@bertram-scharpf.de>:
> Hi,
>
> Am Montag, 25. Mai 2009, 17:30:43 +0900 schrieb Robert Klemme:
>> 2009/5/25 Mohit Sindhwani <mo_mail@onghu.com>:
>> > Jagadeesh wrote:
>> >> [sample perl code]
>> >> $CMD = join('  ',  $cmd, $arg1, $arg2, $arg3);
>> >>
>> > Not 100% sure of what you need, but I think this will do the job for you:
>> > str = [cmd, arg1, arg2, arg3].join(' ')
>>
>> If this is for executing an external process, there is no need to lump
>> all these together, instead you can do which has the advantage that
>> you do not need a shell to parse the individual arguments and also
>> whitespace cannot cause trouble.
>>
>> system cmd, arg1, arg2, arg3
>
> There are two more advantages: Arguments that contain spaces
> remain one argument.

That's what I meant (see above).

> Arguments that contain shell operators like
> ; && || `...` could produce malicious side effects.

Hehe, true!

> Another approach:
>
>  args = [ arg1, arg2, arg3]
>  system cmd, *args

What advantage would it have to first create that array 'args'?

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
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