Are there any good / interesting analogs to regular expressions in 2d?

Question

Are there any good (or at least interesting but flawed) analogs to regular expressions in two dimensions?

In one dimension I can write something like /aaac?(bc)*b?

Answer 1

Regular expressions are designed to model patterns in one dimension. As I understand it, you want to match patterns in a two dimensional array of characters.

Can you use regular expressions? That depends on whether the property that you are searching for is decomposable into components which can be matched in one dimension or not. If so, you can run your regular expressions on columns and rows, and look for intersections in the solution sets from those. Depending on the particular problem you have, this may either solve the problem, or it may find areas in your 2d array which are likely to be solutions.

Whether your problem is decomposable or not, I think writing some custom code will be inevitable. But at least it sounds like an interesting problem, so the work should be pleasant.