The following isprogram the prototypicalprints [["Hello,_World!"_program|Hello World]] programwhen writtencompiled inand Flixexecuted:
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The type and effect signature of the <code>main</code> function specifies that it takes no argumentsparameters, returns thea value of type <code>Unit</code> value, and that the function is impure. The <code>main</code> function must be declared asis impure sincebecause it invokes the <code>printLine</code> function which iscauses itselfan marked as impureeffect.
