Why does [1..5] in Rascal return [1,2,3,4]?

Question

I expect it to return [1,2,3,4,5] as in Haskell.

The manual says it should be inclusive: http://www.meta-environment.org/doc/books/analysis/rascal-manual/rascal-manual.html#id1142539 http://tutor.rascal-mpl.org/Rascal/Rascal.html#/Rascal/Expressions/Values/Range/Range.html — Rup, Sep 05 '13 at 10:06

Jurgen Vinju · Accepted Answer · 2014-01-07T08:28:32.917

9

Short answer: the left index is inclusive and the right is exclusive by design.

Long answer: the reason for the short answer is that lists are zero indexed, and we noticed everybody having to write (or forgetting to write) [0..size(myList) - 1]. Now we can write [0..size(myList)] instead. It is not like Haskell, but its like Python.

edited Jan 07 '14 at 08:28

answered Sep 05 '13 at 10:52

Jurgen Vinju

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Why does [1..5] in Rascal return [1,2,3,4]?

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