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Statement chaining

Syntax

Use backslash \ for line continuation:

<statement>\
<statement>\
<statement>

Compilation

Chained statements are compiled to single-line BASIC with colon separators:

rem Source
poke 53280,0\
poke 53281,0\
poke 646,1

rem Output
poke53280,0:poke53281,0:poke646,1

Advantages

  • Source readability: Break complex sequences into logical lines
  • Output efficiency: Single-line execution is faster on C64
  • Space optimization: Reduces line number overhead
  • Debugging: Each source line maps to single output line

Constraints

  • Continuation must be last character on line (trailing spaces after \ are automatically removed)
  • Cannot chain across scope boundaries
  • Cannot chain label definitions
  • Final statement in chain must not have trailing \
  • Cannot include REM or ; comments in chains - see warning below

Automatic whitespace trimming

BPP+ automatically removes trailing whitespace before processing line continuation:

poke 53280,0  \         rem Spaces after \ are automatically removed
poke 53281,0

Result: poke 53280,0:poke 53281,0

This means you don't need to worry about accidental trailing spaces breaking your line continuations.

Comments and line continuation

Do not use comments in statement chains

Comments (REM and ;) should NOT be used with line continuation (\). This creates either removal of the entire chain or code that doesn't execute. Always place comments before or after the chain, never inside.

See Comment placement for detailed explanation of REM behavior and why this occurs.

Line-length and string limits

  • Native editor limit: BASIC lines longer than ~80 characters may be truncated or become uneditable
  • String limit: A single string literal (e.g., in print) can be up to 255 characters
  • Chaining impact: Since chained statements compile into a single BASIC line, long chains or large print strings can exceed the editor limit. Keep chains reasonably short

See also