[erlang-questions] QLC limitation: early evalutation of list expressions
Andras Georgy Bekes
Wed Aug 6 17:37:16 CEST 2008
In the QLC doc, I read:
"The evaluation of a query handle begins by ... Next all list
expressions [query handle or a list] are evaluated."
So while you can write this in a list comprehension:
[ X || N <- ListExpression, X <- ListExpressionUsingN ].
you can't write this in QLC.
What is the real reason of this behaviour? Only performance, or
Are there any ways to circumvent this, besides writing
qlc:append([[X || X <- ListExpressionUsingN] || N <- ListExpression ]).
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