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Bash regex help

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# 8  
Old 10-10-2012
At some point between version 3 and version 4, bash began to treat a quoted right-hand operand of =~ as a string instead of a pattern. This explains why it used to work one way and now it works another.

Regards,
Alister
# 9  
Old 10-10-2012
If I use the code below without the double and single quotes Test Name is invalid.


Code:
if [[ "$givenName" =~ ^[A-Z]([a-z]|[A-Za-z])+\s+[A-Z]([a-z]|[A-Za-z])+(-[A-Z]([a-z]|[A-Za-z])+)*$ ]]
  then
    echo -e "${bldgrn}$givenName is a valid name.${txtrst}"
else
    echo -e "${bldred}$givenName is an invalid name!!${txtrst}"
exit 1
fi

# 10  
Old 10-10-2012
Try replacing \s with [[:space:]]
This User Gave Thanks to Scrutinizer For This Post:
woodson2
# 11  
Old 10-10-2012
Quote:
Originally Posted by Scrutinizer
Try replacing \s with [[:space:]]
This is perfect. It actually works better that it did before because now a hyphenated last name is now valid as well.

Thank you.

I guess I'm going to have to do some more reading on regular expressions so I can understand them better. Do you have any recommendations on a resource?
# 12  
Old 10-10-2012
Quote:
Originally Posted by alister
At some point between version 3 and version 4, bash began to treat a quoted right-hand operand of =~ as a string instead of a pattern. This explains why it used to work one way and now it works another.
From Bash CHANGELOG:
Quote:
This document details the changes between this version, bash-4.0-alpha,
and the previous version, bash-3.2-release.

....

b. Fixed problems parsing arguments to the [[ command's =~ regular expression
matching operator: metacharacter and whitespace parsing.
This User Gave Thanks to fpmurphy For This Post:
alister
# 13  
Old 10-11-2012
I wasn't aware of that, fpmurphy. Thanks for pointing it out. What I was remembering was:
Quote:
This document details the changes between this version, bash-3.2-alpha,
and the previous version, bash-3.1-release.

...

f. Quoting the string argument to the [[ command's =~ operator now forces
string matching, as with the other pattern-matching operators.
Regards,
Alister
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