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discard """
output: '''
yes
'''
"""
import macros
macro `case`(n: tuple): untyped =
result = newTree(nnkIfStmt)
let selector = n[0]
for i in 1 ..< n.len:
let it = n[i]
case it.kind
of nnkElse, nnkElifBranch, nnkElifExpr, nnkElseExpr:
result.add it
of nnkOfBranch:
for j in 0..it.len-2:
let cond = newCall("==", selector, it[j])
result.add newTree(nnkElifBranch, cond, it[^1])
else:
error "custom 'case' for tuple cannot handle this node", it
var correct = false
case ("foo", 78)
of ("foo", 78):
correct = true
echo "yes"
of ("bar", 88): echo "no"
else: discard
doAssert correct
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