[Larceny-users] (srfi :39 parameters) parameterize evaluating parameter expressions too many times

[Derick Eddington]

According to SRFI 39, the parameter expressions must be evaluated only
once per parameterize evaluation.

Larceny v0.97a4 (alpha test) (Mar 17 2009 11:29:20, precise:Linux:unified)
larceny.heap, built on Tue Mar 17 11:33:15 PDT 2009
ERR5RS mode (no libraries have been imported)

> (import
    (rnrs base)
    (rnrs io simple)
    (srfi :39 parameters))
Autoloading (srfi :39 parameters)

> (define k)

> (define p (make-parameter 1))

> (parameterize (((begin (display "param expr\n") p)
                  (begin (display "value expr\n") 2)))
    (call/cc (lambda (cc) (set! k cc) 'first)))
value expr
param expr
param expr
param expr
param expr
first

> (k 'second)
param expr
param expr
param expr
param expr
second

> 

-- 
: Derick
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