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Re: a bug Sebastian Egner 22 Jul 2005 07:07 UTC

Hello Joo ChurlSoo,

The order of evaluation of the expressions used to
initialize bindings in LET is explicitly left
unspecified in the Scheme standard, Section 4.2.2:

    "Semantics: The <init>s are evaluated in the
current environment (in some unspecified order), ..."

(Consider for example
http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-7.html#%25_sec_4.2.2)

This means your programs should not rely on a
particular ordering of the bindings.

The difference becomes apparent in SRFI-LET because my
reference implementation uses this freedom to
recognize ordinary single-value bindings and collect
them into an ordinary LET.

Sebastian.

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