2001-07-10 14:25:50 +00:00
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#!/bin/bash
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# Indirect variable referencing.
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# This has a few of the attributes of references in C++.
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a=letter_of_alphabet
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letter_of_alphabet=z
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2001-09-04 13:27:31 +00:00
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echo "a = $a" # Direct reference.
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2001-07-10 14:25:50 +00:00
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2001-09-04 13:27:31 +00:00
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echo "Now a = ${!a}" # Indirect reference.
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2008-11-23 22:43:47 +00:00
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# The ${!variable} notation is more intuitive than the old
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#+ eval var1=\$$var2
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2001-07-10 14:25:50 +00:00
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echo
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t=table_cell_3
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table_cell_3=24
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2004-02-16 17:21:02 +00:00
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echo "t = ${!t}" # t = 24
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2001-07-10 14:25:50 +00:00
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table_cell_3=387
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2001-09-04 13:27:31 +00:00
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echo "Value of t changed to ${!t}" # 387
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2008-11-23 22:43:47 +00:00
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# No 'eval' necessary.
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2001-09-04 13:27:31 +00:00
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2004-02-16 17:21:02 +00:00
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# This is useful for referencing members of an array or table,
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#+ or for simulating a multi-dimensional array.
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2005-03-21 13:51:11 +00:00
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# An indexing option (analogous to pointer arithmetic)
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#+ would have been nice. Sigh.
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2001-07-10 14:25:50 +00:00
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exit 0
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2008-07-20 23:16:47 +00:00
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# See also, ind-ref.sh example.
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