Re^4: How to avoid an alphabet and integer next to it in a string?

in reply to Re^3: How to avoid an alphabet and integer next to it in a string?
in thread How to avoid an alphabet and integer next to it in a string?

The Problem with s/H\d*//g is that it will also remove the H from HgS (ok,, not organic chemistry, but you get the point).

One way to avoid that is to use a negative look-ahead:

s/H(?![a-z])\d*//</c>

<p>Or if you prefer the Unicode-y approach:</p>

<code>s/H(?!\p{Ll})\d*//
[download]

Perl 6 - the future is here, just unevenly distributed

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Re^5: How to avoid an alphabet and integer next to it in a string? by piscean (Acolyte) on Mar 21, 2014 at 18:38 UTC
The first code says Forbidden chars again. Second one, Unicode -y approach? I am not familiar with that. Could you help me? How should the input be in an unicode -y approach?	[reply]
Re^6: How to avoid an alphabet and integer next to it in a string? by runrig (Abbot) on Mar 21, 2014 at 18:45 UTC
The first code says Forbidden chars again. So show the input and output, quit making us guess (and when I say 'output' I mean the new string, not the number you're trying to calculate). As far as which approach, don't worry about it. Just pick one (as long as it works).	[reply]
Re^7: How to avoid an alphabet and integer next to it in a string? by piscean (Acolyte) on Mar 21, 2014 at 18:52 UTC
Input was `my $molform = <STDIN>;` [download] C6H9 and Output was: `------Please enter single letter elements in caps only------ Enter the molecular formula of the compound = C6H9 Forbidden chars The molecular weight of the above compound is =` [download]	[reply] [d/l] [select]
Re^8: How to avoid an alphabet and integer next to it in a string? by runrig (Abbot) on Mar 21, 2014 at 19:25 UTC
Re^9: How to avoid an alphabet and integer next to it in a string? by piscean (Acolyte) on Mar 21, 2014 at 19:40 UTC
Re^8: How to avoid an alphabet and integer next to it in a string? by hazylife (Monk) on Mar 21, 2014 at 18:55 UTC
Re^9: How to avoid an alphabet and integer next to it in a string? by runrig (Abbot) on Mar 21, 2014 at 19:20 UTC
Some notes below your chosen depth have not been shown here
Re^5: How to avoid an alphabet and integer next to it in a string? by hazylife (Monk) on Mar 21, 2014 at 18:29 UTC
will also remove the H from HgS Yes, you're right, I stand corrected.	[reply]
Re^5: How to avoid an alphabet and integer next to it in a string? by DrHyde (Prior) on Mar 25, 2014 at 11:26 UTC
Or simpler, H\d+. \d* will match zero or more digits, \d+ matches one or more. update: oh, wait, ignore me. You need to knock out the H in (eg) NaOH, which doesn't have a digit after it.	[reply]

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