Debugging compiler errors
Use diagnostics, line numbers, and generated output to fix pseudocode syntax and logic problems.
Updated 2026-05-04
Read the first error first
Syntax problems often cascade. Fix the earliest error, run again, and then move to the next diagnostic.
Line and column details point to where the compiler first noticed the problem, which may be slightly after the actual typo.
Check declarations and block endings
Many beginner errors come from using an undeclared variable, mixing value types, or forgetting an ENDIF, NEXT, ENDWHILE, or UNTIL.