BASIC Diff

(Taken out of printing)

Colin asked an important question:

Is there a way of comparing a squeezed BASIC file with the original?

This is something I’ve been thinking about recently, because there’s significant difficulties DIFFing BASIC programs, not least because of auto-renumbering in editors.

What would be needed is a semantic diff that cares not for non-syntactic spaces, line numbers and non-syntactic line concatenation, and spots pertinent changes in the code. Give it the ability to map symbol names too (i.e. “aa” in file1 appears to be “longvarname” in file2) and ignore REMs and other deleteables and it would be very powerful.

Good question.

Druck advised

My takeaway is just don’t compress BASIC programs

My feeling is that symbol length will not really make much difference to SCT collisions beyond the smallest of loops. But the perennial paucity of PROC/FN lists (there’s 54 lists for variables but only one for PROCs as standard1) means that short PROC/FN names are more important than short variable names.