New search rules

[gbtami]

Now scoutfish can search for positions where we expect given pieces exist on given squares using "sub-fen" but not for patterns where given piece exist on given rank/file or it's not there at all. Simple example is "white has an isolated a pawn" meaning white has a pawn somewhere in a2-a7 but not in b2-b7. It would be nice to have some syntax/rule to search for this kind of patterns.

[gbtami]

A screenshot showing an isolated a pawn pattern in scid gui.

[mcostalba]

Pawns can have many properties: isolated, passed, doubled, etc..

Your request is a special case of a more general properties on pawns.

[gbtami]

The isolated pawn was just an example. In "piece (not)exist on rank/file" pattern piece can be any type. Another example can be "connected rooks on rank 7" etc.