name=value or -n value? (Visual Ambiguity)
idallen at watmath.UUCP
idallen at watmath.UUCP
Fri Mar 23 15:59:57 AEST 1984
Here's one reason I prefer "name=value" over "-name value".
A command that looks like:
bleen -name value1 value2
is syntactically ambiguous. You have to "know" whether "-name" does or does
not take a following "value1" parameter. This means you have to know the
semantic behaviour of the "-name" flag to know whether BLEEN is receiving
both VALUE1 and VALUE2. It also means the potential for error is greater
with "-name value", since the "-name" might eat up one of the otherwise
independent arguments if someone thinks it doesn't take a following parameter.
This syntax ambiguity isn't present with the syntax form:
bleen name=value1 value2
I need know nothing about any of the parameters to tell that BLEEN is
receiving only one unflagged parameter: VALUE2. Since there is no
ambiguity, I can't accidentally create a semantically meaningful command
if I misunderstand the behaviour of "name=". If "name" doesn't take a
parameter, then "name=value" would be flagged as an error. If "name"
does take a parameter, and I try to use it without one, this would again
be flagged as an error. With "-name value", the program can't tell.
I prefer the syntactic un-ambiguity.
--
-IAN! (Ian! D. Allen) University of Waterloo
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