Maybe I don't understand correctly...but what about 
$teststring =~ /^[[]?([^] _]+)/;

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this puts in $1 the first word of the string, where "word" means "the first sequence of letters ended by "]", " " or "_". Add other delimiters if needed. In the case of "]", it also checks for an optional leading "[".

In reply to Re: Problem with RegEx & various "endings" by waldner
in thread Problem with RegEx & various "endings" by timesink

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