Regular expression to match string starting with a specific word
If you wish to match only lines beginning with stop, use
^stop
If you wish to match lines beginning with the word stop followed by a space:
^stop\s
Or, if you wish to match lines beginning with the word stop, but followed by either a space or any other non-word character you can use (your regex flavor permitting)
^stop\W
On the other hand, what follows matches a word at the beginning of a string on most regex flavors (in these flavors \w matches the opposite of \W)
^\w
If your flavor does not have the \w shortcut, you can use
^[a-zA-Z0-9]+
Be wary that this second idiom will only match letters and numbers, no symbol whatsoever.
Check your regex flavor manual to know what shortcuts are allowed and what exactly do they match (and how do they deal with Unicode).
Try this:
/^stop.*$/
Explanation:
- / charachters delimit the regular expression (i.e. they are not part of the Regex per se)
- ^ means match at the beginning of the line
- . followed by * means match any character (.), any number of times (*)
- $ means to the end of the line
If you would like to enforce that stop be followed by a whitespace, you could modify the RegEx like so:
/^stop\s+.*$/
- \s means any whitespace character
- + following the \s means there has to be at least one whitespace character following after the stop word
Note: Also keep in mind that the RegEx above requires that the stop word be followed by a space! So it wouldn't match a line that only contains: stop