Close, not quite. The "quantifier" (i.e. ?,+,*) appear AFTER the "atom" (i.e. char or special symbol).
The syntax is also off a bit. It should be =~ and /../ (not single ticks). $result =~ /^ *-?[0-9]+[.]?[0-9]* *\$/; ^ = beginning of line (also called an anchor) * = zero or more spaces (not whitespace). I suggest using \s* instead, which is zero or more whitespace (includes spaces, tabs, returns, and newlines in some situations) -? = Matches an optional "-" char (0 or 1 times). [0-9]+ = 1 or more numbers (use \d+ instead) [.]? = optional char (any char). Brackets not needed, use .? instead. [0-9]* = 0 or more digits, again use \d* instead. * = 0 or more spaces, again use \s* instead. \$ = matches an actual "$" char. So the new regex looks like this... $result =~ /^\s*-?\d+.?\d*\s*\$/; Or using the "x" modifier (a good thing to do) to space it out, and add comments... $result =~ / ^ # start of string \s* # 0+ whitespace -? # 0-1 "-" \d+ # 1+ digits .? # 0-1 any char \d* # 0+ digits \s* # 0+ whitespace \$ # "$" char /x; The regex is starting to look like it is supposed to match numbers like 21.25$ and -50.00. ...In which case the ".?" is supposed to be a real period, not an "any char". If it should be a real period (or decimal point), use "\.?" instead. Rob -----Original Message----- From: Johnson, Shaunn [mailto:[EMAIL PROTECTED] Sent: Thursday, October 02, 2003 5:20 PM To: [EMAIL PROTECTED] Subject: explain regex statement? Howdy: I have a statement and I'm trying to see if I understand what it is really is doing (not my code). The code does this: [snip] result ~ '^ *-?[0-9]+[.]?[0-9]* *\$' [/snip] I break out the meaning as this: [snip example] ^ = beginning of line plus a white space *- = everything up to, and including, to the ' - ' ?[0-9] = 1 or 0 times of a number +[.] = 1 or more times any character ?[0-9]* *\$ = 1 or more times any number plus any other character and a white space and then any MORE characters to the end of the line [/snip example] How far off am I? Thanks! -X -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
