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Full Discussion: Indirect variables in Bash
Top Forums Shell Programming and Scripting Indirect variables in Bash Post 302769197 by Corona688 on Monday 11th of February 2013 12:51:12 PM
Old 02-11-2013
Kind of exactly how I've shown you.

Code:
A="abc"
B="def"

read $A$B <<<"string"

...should put the string "string" into the variable named abcdef.

This is how it's often used:
Code:
read VARNAME

...but note that it takes a variable name -- a string -- not the variable itself. You can feed it whatever string you please, derived from whatever variables you please, and do things that would otherwise require ugly insecure eval hacks.

You can redirect into it any way you please. <<< is an ordinary redirection in BASH which replaces stdin with a string.
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Char(3) 						User Contributed Perl Documentation						   Char(3)

NAME
PDL::Char -- PDL subclass which allows reading and writing of fixed-length character strings as byte PDLs SYNOPSIS
use PDL; use PDL::Char; my $pchar = PDL::Char->new( [['abc', 'def', 'ghi'],['jkl', 'mno', 'pqr']] ); $pchar->setstr(1,0,'foo'); print $pchar; # 'string' bound to "", perl stringify function # Prints: # [ # ['abc' 'foo' 'ghi'] # ['jkl' 'mno' 'pqr'] # ] print $pchar->atstr(2,0); # Prints: # ghi DESCRIPTION
This subclass of PDL allows one to manipulate PDLs of 'byte' type as if they were made of fixed length strings, not just numbers. This type of behavior is useful when you want to work with charactar grids. The indexing is done on a string level and not a character level for the 'setstr' and 'atstr' commands. This module is in particular useful for writing NetCDF files that include character data using the PDL::NetCDF module. FUNCTIONS
new Function to create a byte PDL from a string, list of strings, list of list of strings, etc. # create a new PDL::Char from a perl array of strings $strpdl = PDL::Char->new( ['abc', 'def', 'ghij'] ); # Convert a PDL of type 'byte' to a PDL::Char $strpdl1 = PDL::Char->new (sequence (byte, 4, 5)+99); $pdlchar3d = PDL::Char->new([['abc','def','ghi'],['jkl', 'mno', 'pqr']]); string Function to print a character PDL (created by 'char') in a pretty format. $char = PDL::Char->new( [['abc', 'def', 'ghi'], ['jkl', 'mno', 'pqr']] ); print $char; # 'string' bound to "", perl stringify function # Prints: # [ # ['abc' 'def' 'ghi'] # ['jkl' 'mno' 'pqr'] # ] # 'string' is overloaded to the "" operator, so: # print $char; # should have the same effect. setstr Function to set one string value in a character PDL. The input position is the position of the string, not a character in the string. The first dimension is assumed to be the length of the string. The input string will be null-padded if the string is shorter than the first dimension of the PDL. It will be truncated if it is longer. $char = PDL::Char->new( [['abc', 'def', 'ghi'], ['jkl', 'mno', 'pqr']] ); $char->setstr(0,1, 'foobar'); print $char; # 'string' bound to "", perl stringify function # Prints: # [ # ['abc' 'def' 'ghi'] # ['foo' 'mno' 'pqr'] # ] $char->setstr(2,1, 'f'); print $char; # 'string' bound to "", perl stringify function # Prints: # [ # ['abc' 'def' 'ghi'] # ['foo' 'mno' 'f'] -> note that this 'f' is stored "f" # ] atstr Function to fetch one string value from a PDL::Char type PDL, given a position within the PDL. The input position of the string, not a character in the string. The length of the input string is the implied first dimension. $char = PDL::Char->new( [['abc', 'def', 'ghi'], ['jkl', 'mno', 'pqr']] ); print $char->atstr(0,1); # Prints: # jkl perl v5.12.1 2009-10-17 Char(3)
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