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/*-*-Macsyma-*-*/
/*
CASEQ(<var>,'[<keys1>],<stmt1>,
'[<keys2>],<stmt2>,
....,
'[<keysn>],<stmtn>
{,'otherwise,<code for no match>})
where the first <stmt> that has <var> as a member of the associated
<keys> is the one chosen to execute. */
sstatus(feature,"gcook caseq")$
caseq(var,[pairs])::=
if length(pairs)<=2 then
block([keys:first(pairs),statement:last(pairs)],
if keys=otherwise then buildq([var,statement],statement)
else buildq([var,keys,statement],if member(var,'keys) then statement))
else buildq([var,keys:first(pairs),statement:first(rest(pairs)),
pairs:rest(rest(pairs))],
if member(var,'keys) then statement else caseq(var,splice(pairs)))$
push(c,l)::=(if symbolp(x) then x else error("arg must be a symbol",x),
buildq([c,l],l:cons(c,l)))$
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