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[Scheme-reports] strange language in spec of `and' and `or'
- To: scheme-reports <scheme-reports@x>
- Subject: [Scheme-reports] strange language in spec of `and' and `or'
- From: Andy Wingo <wingo@x>
- Date: Thu, 19 May 2011 17:55:47 +0200
Section 4.2.1, p. 11, in the spec of `and':
"The TEST expressions are evaluated from left to right, and the value
of the first expression that evaluates to a false value (see section
6.3.1) is returned. Any remaining expressions are not evaluated. If
all the expressions evaluate to true values, the value of the last
expression is returned..."
Why these weasel words? Is this to somehow permit implementations with
more than one false value to return a false value from `and' which is
not #f ?
Likewise, `or' has similar language.
Suggestion: Replace "the value of the first expression that evaluates to
a false value (see section 6.3.1)" with "returning `#f' if any
expression evaluates to a false value".
Dunno :)
Andy
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