In Mathematica the FullForm of a && b is And[a, b]. You can use this to ... | Hacker News

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carlob on May 24, 2013 | parent | context | favorite | on: Ifs and &&s and Plan 9's Source Code

In Mathematica the FullForm of a && b is And[a, b]. You can use this to format long lists of conditions as

    And[
        a,
        b
    ]

You can also rely on the fact that logical expressions are always short-circuited, so False && Print["won't be printed"], doesn't print anything.

Finally, you can put a bunch of conditions in a list and do And @@ list.

klez on May 25, 2013 [–]

> You can also rely on the fact that logical expressions are always short-circuited, so False && Print["won't be printed"], doesn't print anything.

This is true for any language I can think of.

E.g. in perl

    open(my $fh, "<", "input.txt")
        or die "cannot open < input.txt: $!";

is idiomatic

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