Re: Re: Matching floats according to perlfaq4

[Anonymous Monk]

/^([+-]?)(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?$/

==

/^[+-]?(\d+\.\d*|\d*\.\d+)(e[+-]?\d+)?$/i

The look-ahead is to ensure that a '.' on its own isn't matched, but that (eg) '.04' and '4.' is. I'm not sure how correct the latter form is. The e+3, E-2 etc bit may or may not match; I don't think (example) '1.2e' on its own is meaningful.

[Anonymous Monk]

...and of course I meant

/^ [+-]? ( \d+ (\.\d*)? | \.\d+ ) (e[+-]?\d+)? $/ix

... really (whitespace added for readability)

[demerphq]

Of course it wont match 1.2e so that isnt a worry. And 4. certainly is meaningful (to perl anwyay). Try it...

Also as I pointed out in my earlier reply the two regexes are _not_ == to each other. They are similar in that they match or reject similar data, however the parts that they match and the way they get captured for later use are radically different.

For instance

/([A-Za-z_0-9])(\w)(\w)/

matches/rejects the same data as

/(\w{3})/

But the utility of the two is totally different....

:-)

--- demerphq
my friends call me, usually because I'm late....