18 lines
414 B
Text
18 lines
414 B
Text
:- module env_var.
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:- interface.
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:- import_module io.
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:- pred main(io::di, io::uo) is det.
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:- implementation.
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:- import_module maybe, string.
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main(!IO) :-
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io.get_environment_var("HOME", MaybeValue, !IO),
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(
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MaybeValue = yes(Value),
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io.write_string("HOME is " ++ Value ++ "\n", !IO)
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;
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MaybeValue = no,
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io.write_string("environment variable HOME not set\n", !IO)
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).
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