tasks a-s

2013-04-10 23:57:08 -07:00 · 2013-04-10 23:57:08 -07:00 · b83f433714
commit b83f433714
parent 47bf37c096
12433 changed files with 156208 additions and 123 deletions
--- a/Task/Environment-variables/Mercury/environment-variables.mercury
+++ b/Task/Environment-variables/Mercury/environment-variables.mercury
@ -0,0 +1,18 @@
+:- module env_var.
+:- interface.
+
+:- import_module io.
+:- pred main(io::di, io::uo) is det.
+
+:- implementation.
+:- import_module maybe, string.
+
+main(!IO) :-
+    io.get_environment_var("HOME", MaybeValue, !IO),
+    (
+        MaybeValue = yes(Value),
+        io.write_string("HOME is " ++ Value ++ "\n", !IO)
+    ;
+        MaybeValue = no,
+        io.write_string("environment variable HOME not set\n", !IO)
+    ).