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5933aece9b
* `caseStmtMacros` no longer experimental, experimental manual refactor * Update doc/manual.rst * apply review suggestions * apply review Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
34 lines
649 B
Nim
34 lines
649 B
Nim
discard """
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output: '''
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yes
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'''
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"""
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import macros
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macro `case`(n: tuple): untyped =
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result = newTree(nnkIfStmt)
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let selector = n[0]
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for i in 1 ..< n.len:
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let it = n[i]
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case it.kind
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of nnkElse, nnkElifBranch, nnkElifExpr, nnkElseExpr:
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result.add it
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of nnkOfBranch:
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for j in 0..it.len-2:
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let cond = newCall("==", selector, it[j])
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result.add newTree(nnkElifBranch, cond, it[^1])
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else:
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error "custom 'case' for tuple cannot handle this node", it
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var correct = false
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case ("foo", 78)
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of ("foo", 78):
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correct = true
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echo "yes"
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of ("bar", 88): echo "no"
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else: discard
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doAssert correct
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