A $(( expression )) bug? Post: 302982732

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Top Forums UNIX for Advanced & Expert Users A $(( expression )) bug? Post 302982732 by wisecracker on Monday 3rd of October 2016 10:55:14 AM

10-03-2016

Registered User

Hi drl...
How about this then:-
$[ ( expression ) ] is runtime identical to $(( expression )) , yes...
If the error reports are different then does that imply that they might not be runtime identical?
If not then explain why some of these errors are different?
These old arithmetic expressions were what brought about this thread in the first place.

Code:

Last login: Mon Oct  3 14:53:41 on console
AMIGA:barrywalker~> txt="12345"
AMIGA:barrywalker~> echo "$(( # = txt ))"
-bash: bad substitution: no closing `)' in "$(( # = txt ))"
AMIGA:barrywalker~> echo "$[ ( # = txt ) ]"
-bash: ( # = txt ) : syntax error: operand expected (error token is "# = txt ) ")
AMIGA:barrywalker~> echo "$(( # = $txt ))"
-bash: bad substitution: no closing `)' in "$(( # = $txt ))"
AMIGA:barrywalker~> echo "$[ ( # = $txt ) ]"
-bash: ( # = 12345 ) : syntax error: operand expected (error token is "# = 12345 ) ")
AMIGA:barrywalker~> echo "$(( $# = $txt ))"
-bash: 0 = 12345 : attempted assignment to non-variable (error token is "= 12345 ")
AMIGA:barrywalker~> echo "$[ ( $# = $txt ) ]"
-bash: ( 0 = 12345 ) : attempted assignment to non-variable (error token is "= 12345 ) ")
AMIGA:barrywalker~> echo "$(( $# = txt ))"
-bash: 0 = txt : attempted assignment to non-variable (error token is "= txt ")
AMIGA:barrywalker~> echo "$[ ( $# = txt ) ]"
-bash: ( 0 = txt ) : attempted assignment to non-variable (error token is "= txt ) ")
AMIGA:barrywalker~> bash --version
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin15)
Copyright (C) 2007 Free Software Foundation, Inc.
AMIGA:barrywalker~> _

At this pont I am going to bow out gracefully and keep a watchful eye on this thread.

wisecracker

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