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tuple unpacking works in a non-var/let context

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Araq 2015-08-21 12:31:55 +02:00
commit bfd2fd67f9
5 changed files with 69 additions and 2 deletions
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26
compiler/lowerings.nim
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@ -63,6 +63,32 @@ proc lowerTupleUnpacking*(n: PNode; owner: PSym): PNode =
if n.sons[i].kind == nkSym: v.addVar(n.sons[i])
result.add newAsgnStmt(n.sons[i], newTupleAccess(tempAsNode, i))
proc newTupleAccessRaw*(tup: PNode, i: int): PNode =
result = newNodeI(nkBracketExpr, tup.info)
addSon(result, copyTree(tup))
var lit = newNodeI(nkIntLit, tup.info)
lit.intVal = i
addSon(result, lit)
proc lowerTupleUnpackingForAsgn*(n: PNode; owner: PSym): PNode =
let value = n.lastSon
result = newNodeI(nkStmtList, n.info)
var temp = newSym(skTemp, getIdent(genPrefix), owner, value.info)
var v = newNodeI(nkLetSection, value.info)
let tempAsNode = newIdentNode(getIdent(genPrefix & $temp.id), value.info)
var vpart = newNodeI(nkIdentDefs, tempAsNode.info, 3)
vpart.sons[0] = tempAsNode
vpart.sons[1] = ast.emptyNode
vpart.sons[2] = value
addSon(v, vpart)
result.add(v)
let lhs = n.sons[0]
for i in 0 .. lhs.len-1:
result.add newAsgnStmt(lhs.sons[i], newTupleAccessRaw(tempAsNode, i))
proc lowerSwap*(n: PNode; owner: PSym): PNode =
result = newNodeI(nkStmtList, n.info)
# note: cannot use 'skTemp' here cause we really need the copy for the VM :-(