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bash regex =~ case insensetive, possible?

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# 1  
Old 05-21-2009
Question bash regex =~ case insensetive, possible?
It can get very annoying that bash regex =~ is case-sensetive, is there a way to set it to be case-insensetive?

Code:
if [[ "$1" =~ "(test)" ]]; then
  echo match
else 
  echo no match
fi

# 2  
Old 05-21-2009
Quote:
Originally Posted by TehOne
It can get very annoying that bash regex =~ is case-sensetive, is there a way to set it to be case-insensetive?

A few seconds with the bash man page reveals:

Code:
shopt -s nocasematch

Quote:
Code:
if [[ "$1" =~ "(test)" ]]; then
  echo match
else 
  echo no match
fi


You are not testing against a regex; you are testing against a string. To test a regex, remove the quotes from the right-hand side.
# 3  
Old 05-21-2009
Quote:
Originally Posted by cfajohnson

A few seconds with the bash man page reveals:

Code:
shopt -s nocasematch


You are not testing against a regex; you are testing against a string. To test a regex, remove the quotes from the right-hand side.

It doesn't work, here's how I tested it:

Code:
if [[ "$1" =~ "(test)" ]]; then
  echo match with quotas
else
  echo no match with quotas
fi

if [[ "$1" =~ \(test\) ]]; then
  echo match without quotas
else
  echo no match without quotas
fi

Code:
[21:56:45] root:~# shopt -s nocasematch
[21:59:29] root:~# ./test Test
no match with quotas
no match without quotas

Edit:

Code:
GNU bash, version 3.1.17(1)-release (x86_64-pc-linux-gnu)

Last edited by TehOne; 05-21-2009 at 05:15 PM..
# 4  
Old 05-21-2009
Code:
if [[ "$1" =~ (test) ]]; then
  echo match
else
  echo no match
fi

# 5  
Old 05-21-2009
Quote:
Originally Posted by cfajohnson
Code:
if [[ "$1" =~ (test) ]]; then
  echo match
else
  echo no match
fi

./test: line 10: unexpected argument `(' to conditional binary operator
./test: line 10: syntax error near `(t'
./test: line 10: `if [[ "$1" =~ (test) ]]; then'

I didn't use \( \) for no reason :>

And I have also tested '(test)' and test
# 6  
Old 05-21-2009

It works without the backslashes in bash 3.2 (released almost 3 years ago, in 1996) and later.
# 7  
Old 05-21-2009
Quote:
Originally Posted by cfajohnson

It works without the backslashes in bash 3.2 (released almost 3 years ago, in 1996) and later.
Code:
GNU bash, version 4.0.0(1)-release (x86_64-unknown-linux-gnu)

Code:
if [[ "$1" =~ "(test)" ]]; then
  echo match 1
else
  echo no match 1
fi

if [[ "$1" =~ \(test\) ]]; then
  echo match 2
else
  echo no match 2
fi

if [[ "$1" =~ '(test)' ]]; then
  echo match 3
else
  echo no match 3
fi

if [[ "$1" =~ (test) ]]; then
  echo match 4
else
  echo no match 4
fi

Code:
[23:32:05] root:~# shopt -s nocasematch
[23:32:22] root:~# ./test Test
no match 1
no match 2
no match 3
./test: line 22: unexpected argument `(' to conditional binary operator
./test: line 22: syntax error near `(t'
./test: line 22: `if [[ "$1" =~ (test) ]]; then'

This User Gave Thanks to TehOne For This Post:
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