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12.10 Fast-Load Serialization

The bindings documented in this section are provided by the racket/fasl library, not racket/base or racket.

(s-exp->fasl v [out])  (or/c (void) bytes?)
  v : any/c
  out : (or/c output-port? #f) = #f
(fasl->s-exp in)  any/c
  in : (or/c input-port? bytes?)
The s-exp->fasl function serializes v to a byte string, printing it directly to out if out is an output port or return the byte string otherwise. The fasl->s-exp function decodes a value from a byte string (supplied either directly or as an input port) that was encoded with s-exp->fasl.

The v argument must be a value that could be quoted as a literal, because s-exp->fasl essentially uses (compile `',v) to encode the value using Racket’s built-in fast-load format for bytecode.

The byte-string encoding produced by s-exp->fasl is specific to a version of Racket. That is, the resulting byte string can be decoded back to v only using the same version with which it was encoded.


> (define fasl (s-exp->fasl (list #("speed") 'racer #\!)))
> fasl


> (fasl->s-exp fasl)

'(#("speed") racer #\!)