IMHO:
[AZ_] must be [A-Z_]
the third [AZ_] must be [A-Z0-9_]
I've found: 
s/^\[([A-Z_]+)\s([A-Z_]+)\s([A-Z0-9]+)\/([0-9]+)\]$/$1_$2_$3_$4/g

[download]
ok? :-) It works but it's not an inline-change on $3!

In reply to Re: Substituting in the substitution! by perlinux
in thread Substituting in the substitution! by Mondongo

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