I suggested to someone recently that they reword a sentence (in a web standards specification document, if it matters) to:
Let A be 1 if B is true and C is X, 2 otherwise.
Someone else agreed overall, but said it should be a semicolon:
Let A be 1 if B is true and C is X; 2 otherwise.
To me, that semicolon is out of place and should be a comma. If the bit after "if" had commas in it, then I'd use a semi, but not otherwise. Which should it be?
Interested in AmEng and/or BrEng answers. (My personal dialect is a combination of the two.)
This "if/otherwise" aspect doesn't seem to be covered by the answers to When should one use the comma versus the semicolon, and vice versa?.