The textfile contains text like this 
[Event "?"]
[Result "*"]
[SetUp "1"]
[FEN "4b3/pq2p1k1/1p1pP2R/1P1P2K1/2rp4/8/P5Q1/8 w - - 0 50"]
[PlyCount "0"]
*

[Event "?"]
[Round "39"]
[Result "*"]
[SetUp "1"]
[FEN "5rk1/5p1p/3q2p1/1Rp1n3/P3P3/3Pb1pP/2Q3B1/3R3K b - - 0 1"]

[download]

I want to change [Event "?"] to [Event "Black to move"] if in the line [FEN .... ] I find a space, then b followed by another space

and to change it to [Event "White to move"] if in the line [FEN .... ] I find a space, then w followed by another space

I have tried to use lookahead, but as have not programmed anything in Perl for quite a while with no success.

Sorry for beeing unclear

2017-11-07 Athanasius added code tags

In reply to Re^2: regex replace a string by OldChamp
in thread regex replace a string by OldChamp

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