k... I'm not a RexEx guru either but I'm going to give it a shot,
bolded blue text text will be subject of my explanation when regex expressions are used...
your expression [1-9]|1[0-5]
Scenario A: [1-9]|1[0-5] means match any number 1 thru 9, pretty basic
[1-9]|1[0-5] is a logical operator [OR]
Scenario B:[1-9]|1[0-5] means any number zero thru five
ok now that we broke it down lets look at what your expression would match...
1 = match based on scenario A
2 = match basesed on A
... up to
9 would match!
10 = now comes the fun part the
1 would match Scenario A and since there was a match it doesnt evaluate it under scenario B and
0 gets ignored.
11 = again Scenario A twice and doesn't even get to scenario B
so for it two work you must have it backwards
1[0-5]|[1-9]
and I would even go a step further and make sure the match is not in the middle of a string by adding
^ in the begging of the expression to indicate begining of line or a word and
$ at the end of the expression to indicated end of line or word, like so...
(^1[0-5]$)|(^[1-9]$)
I hope this helps.
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