[erlang-questions] style question - best way to test multiple non-guard conditions sequentially
Wed Jun 19 20:23:49 CEST 2013
Suppose one has multiple conditions that are not guards that need to be
tested sequentially (meaning, only test condition N+1 after condition N
tests false) in a function. Using a case or if in a simplistic way
would then produce considerable nesting, especially as the number of
conditions increases above 2 or 3.
Is there some way in Erlang to write such code without either breaking
up the function clause or using high degrees of nesting?
The closest I can come is something like:
C1 = cond1(...),
C2 = C1 orelse cond2(...),
C3 = C2 orelse cond3(...),
if C1 -> ...;
C2 -> ...;
C3 -> ...;
true -> ...
Which works, but looks rather cryptic. It also seems like it is doing
all of the branching at least twice.
I guess this also implies the question: why does Erlang require the
conditions in an if statement to be guards?
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