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Full Discussion: Indirect variables in Bash
Top Forums Shell Programming and Scripting Indirect variables in Bash Post 302769088 by DFr0st on Monday 11th of February 2013 06:50:46 AM
Old 02-11-2013
Indirect variables in Bash

Hello,
I've spent hours this morning reading various past forum posts and documentation pages but I can't find exactly what I need.

I'm trying to call a variable with a variable in the name without having to make a third variable.

For example:

Code:
path=AB
legAB=50

leg$path

I want to be able to call leg$path variable and get the value "50"


I am aware that if I created another variable I could do this using the ${! } notation:

Code:
var=leg$path
echo ${!var}=50

However, I want to be able to miss out this last step. Is this possible?
Thanks,
Dan

Last edited by DFr0st; 02-11-2013 at 08:05 AM..
 

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RAKE(1) 						 Ruby Programmers Reference Guide						   RAKE(1)

NAME
rake -- Ruby Make SYNOPSIS
rake [--f Rakefile] [--version] [-CGNPgnqstv] [-D [PATTERN]] [-E CODE] [-I LIBDIR] [-R RAKELIBDIR] [-T [PATTERN]] [-e CODE] [-p CODE] [-r MODULE] [--rules] [variable=value] target ... DESCRIPTION
Rake is a simple ruby(1) build program with capabilities similar to the regular make(1) command. Rake has the following features: o Rakefiles (Rake's version of Makefiles) are completely defined in standard Ruby syntax. No XML files to edit. No quirky Makefile syntax to worry about (is that a tab or a space?). o Users can specify tasks with prerequisites. o Rake supports rule patterns to synthesize implicit tasks. o Flexible FileLists that act like arrays but know about manipulating file names and paths. o A library of prepackaged tasks to make building rakefiles easier. OPTIONS
--version Display the program version. -C --classic-namespace Put Task and FileTask in the top level namespace -D [PATTERN] --describe [PATTERN] Describe the tasks (matching optional PATTERN), then exit. -E CODE --execute-continue CODE Execute some Ruby code, then continue with normal task processing. -G --no-system --nosystem Use standard project Rakefile search paths, ignore system wide rakefiles. -I LIBDIR --libdir LIBDIR Include LIBDIR in the search path for required modules. -N --no-search --nosearch Do not search parent directories for the Rakefile. -P --prereqs Display the tasks and dependencies, then exit. -R RAKELIBDIR --rakelib RAKELIBDIR --rakelibdir RAKELIBDIR Auto-import any .rake files in RAKELIBDIR. (default is rakelib ) -T [PATTERN] --tasks [PATTERN] Display the tasks (matching optional PATTERN) with descriptions, then exit. -e CODE --execute CODE Execute some Ruby code and exit. -f FILE --rakefile FILE Use FILE as the rakefile. -h --help Prints a summary of options. -g --system Using system wide (global) rakefiles (usually ~/.rake/*.rake ). -n --dry-run Do a dry run without executing actions. -p CODE --execute-print CODE Execute some Ruby code, print the result, then exit. -q --quiet Do not log messages to standard output. -r MODULE --require MODULE Require MODULE before executing rakefile. -s --silent Like --quiet, but also suppresses the 'in directory' announcement. -t --trace Turn on invoke/execute tracing, enable full backtrace. -v --verbose Log message to standard output (default). --rules Trace the rules resolution. SEE ALSO
ruby(1) make(1) http://rake.rubyforge.org/ REPORTING BUGS
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Rake is written by Jim Weirich <jim@weirichhouse.org> UNIX
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