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Compiler or interpreter?
How to determine if a program is running in the interpreter or as compiled code
Alex Shinn suggested:
(cond-expand (compiling ...) (else ...))
Based on that, John Cowan came with:
(cond-expand (compiling (define (compiled?) #t)) (else (define (compiled?) #f)))
Felix Winkelmann mentioned the test-feature? procedure which can do the proposed job too:
(test-feature? 'script) ; running via csi -s (test-feature? 'compiling) ; running as a compiler extension (-X) (test-feature? 'csi) ; running in csi