What's the difference between \d , [:digit:], and [0-9] in regular expression ?


 
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# 8  
Old 09-01-2011
On fedora 15 :
Code:
[river@localhost Desktop]$ [[ "123" =~ \\b[0-9]{3}\\b ]] && echo "ok" || echo "error"
error
[river@localhost Desktop]$  [[ "123" =~ "\b[0-9]{3}\b" ]] && echo "ok" || echo "error"
error

# 9  
Old 09-01-2011
Word boundaries could be marked also by \< and \>,
did you try that syntax?

Code:
4.1.10(4)-release$ reg='\<[0-9]{3}\>'
4.1.10(4)-release$ [[ "123" =~ $reg ]] && echo "ok" || echo "error"
ok

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