Re: Regex to detect file name

it is easy to do with two regexes, such as:

$f =~ /^[\w\.]+$/ 
&&
$f =~ /^\w/
[download]

The first checks what the entire filename consists of, and the second checks the leading letter. There are endless variations on the same idea.

Comment on Re: Regex to detect file name Download Code

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Re^2: Regex to detect file name by Laurent_R (Canon) on Jul 06, 2018 at 07:40 UTC
it is easy to do with two regexes, such as: ... Easy, perhaps, but wrong. The suggested two regexes would match a string starting with an underscore. `DB<1> $f = "_foo"; DB<2> print "Success" if $f =~ /^[\w\.]+$/ && $f =~ /^\w/; Success DB<3>` [download] Update (at 7:50 UTC): sorry, the last sentence below is wrong, I had missed the $ at the end of the first pattern. ~~It would also accept garbage characters in the middle.~~	[reply] [d/l]
Re^2: Regex to detect file name by Anonymous Monk on Jul 05, 2018 at 21:31 UTC
thats a waste of resources `/^\w[\w\.]*$/` [download]	[reply] [d/l]
Re^3: Regex to detect file name by Anonymous Monk on Jul 06, 2018 at 02:08 UTC
This is not a game of Name That Tune. There are no brownie-points for doing it in one regex versus two. If it does the job, is clear, and easy to maintain, Just Do It.	[reply]
Re^4: Regex to detect file name by Anonymous Monk on Jul 08, 2018 at 01:20 UTC
As if we needed any further proof that you don't actually know how to think like an engineer.	[reply]


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