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Full Discussion: Variable brace expansion
Top Forums UNIX for Dummies Questions & Answers Variable brace expansion Post 302394128 by treesloth on Wednesday 10th of February 2010 01:31:12 PM
Old 02-10-2010
Variable brace expansion
I'm in the habit of using the following type of loop structure:

Code:
for num in `seq $1 $2`
do
     command
done

While `seq $1 $2` is not exactly a huge resource hog, I would like to learn a better way. It seems that brace expansion is a good way to go:

Code:
for num in {3..10}

The problem, though, is that it so far appears that there's no way to use a variable; that is, this doesn't work:

Code:
for num in {$1..$2}

It appears that Bash's order of operations is 1) perform the expansion, then 2) substitute variables, if relevant. In fact, that appears to be a serious roadblock-- Bash expands in such a way that the variable cannot be made to represent a range parameter. So, what's one to do? Brace expansion seems like it should be the lowest-impact method, but it apparently can't be used here. Is there a better way than the seq (or jot, depending on what's available) method?
 

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LEARN ABOUT OSX

locale::codes::currency

Locale::Codes::Currency(3pm)				 Perl Programmers Reference Guide			      Locale::Codes::Currency(3pm)

NAME

       Locale::Codes::Currency - standard codes for currency identification

SYNOPSIS

	   use Locale::Codes::Currency;

	   $curr = code2currency('usd');     # $curr gets 'US Dollar'
	   $code = currency2code('Euro');    # $code gets 'eur'

	   @codes   = all_currency_codes();
	   @names   = all_currency_names();

DESCRIPTION

       The "Locale::Codes::Currency" module provides access to standard codes used for identifying currencies and funds, such as those defined in
       ISO 4217.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 4217
       three-letter codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying currencies. A code set may be specified using either a name, or a
       constant that is automatically exported by this module.

       For example, the two are equivalent:

	  $curr = code2currency('usd','alpha');
	  $curr = code2currency('usd',LOCALE_CURR_ALPHA);

       The codesets currently supported are:

       alpha, LOCALE_CURR_ALPHA
	   This is a set of three-letter (uppercase) codes from ISO 4217 such as EUR for Euro.

	   Two of the codes specified by the standard (XTS which is reserved for testing purposes and XXX which is for transactions where no
	   currency is involved) are omitted.

	   This is the default code set.

       num, LOCALE_CURR_NUMERIC
	   This is the set of three-digit numeric codes from ISO 4217.

ROUTINES

       code2currency ( CODE [,CODESET] )
       currency2code ( NAME [,CODESET] )
       currency_code2code ( CODE ,CODESET ,CODESET2 )
       all_currency_codes ( [CODESET] )
       all_currency_names ( [CODESET] )
       Locale::Codes::Currency::rename_currency  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::Currency::add_currency  ( CODE ,NAME [,CODESET] )
       Locale::Codes::Currency::delete_currency  ( CODE [,CODESET] )
       Locale::Codes::Currency::add_currency_alias  ( NAME ,NEW_NAME )
       Locale::Codes::Currency::delete_currency_alias  ( NAME )
       Locale::Codes::Currency::rename_currency_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::Currency::add_currency_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::Currency::delete_currency_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.iso.org/iso/support/currency_codes_list-1.htm
	   The ISO 4217 data.

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 1997-2001 Canon Research Centre Europe (CRE).
	  Copyright (c) 2001	  Michael Hennecke
	  Copyright (c) 2001-2010 Neil Bowers
	  Copyright (c) 2010-2012 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.16.2							    2012-10-11					      Locale::Codes::Currency(3pm)
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