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3.34 Literal

You cannot POSTPONE numbers:

: [FOO] POSTPONE 500 ; immediate

Instead, you can use LITERAL (compilation: n --; run-time: -- n ):

: [FOO] ( compilation: --; run-time: -- n )
  500 POSTPONE literal ; immediate

: flip [FOO] ;
flip .
see flip

LITERAL consumes a number at compile-time (when it’s compilation semantics are executed) and pushes it at run-time (when the code it compiled is executed). A frequent use of LITERAL is to compile a number computed at compile time into the current word:

: bar ( -- n )
  [ 2 2 + ] literal ;
see bar

Assignment: Write ]L which allows writing the example above as : bar ( -- n ) [ 2 2 + ]L ;