added operateOn to sugar.nim to give Nim the chaining mechanism it de… (#13092)

* implemented the with stdlib module as specified in https://github.com/nim-lang/RFCs/issues/193
* change sugar.outplace to sugar.dup according to https://github.com/nim-lang/RFCs/issues/193
* changelog update
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Andreas Rumpf 2020-02-26 20:36:06 +01:00 • committed by GitHub
commit d55bbefdcc
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4 changed files with 145 additions and 27 deletions

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@ -191,31 +191,41 @@ macro capture*(locals: varargs[typed], body: untyped): untyped {.since: (1, 1).}
result.add(newProc(newEmptyNode(), params, body, nnkProcDef))
for arg in locals: result.add(arg)
macro outplace*[T](arg: T, call: untyped; inplaceArgPosition: static[int] = 1): T {.since: (1, 1).} =
## Turns an `in-place`:idx: algorithm into one that works on
## a copy and returns this copy. The second parameter is the
## index of the calling expression that is replaced by a copy
## of this expression.
## **Since**: Version 1.2.
runnableExamples:
import algorithm
when (NimMajor, NimMinor) >= (1, 1):
import std / private / underscored_calls
var a = @[1, 2, 3, 4, 5, 6, 7, 8, 9]
doAssert a.outplace(sort()) == sorted(a)
#Chaining:
var aCopy = a
aCopy.insert(10)
macro dup*[T](arg: T, calls: varargs[untyped]): T =
## Turns an `in-place`:idx: algorithm into one that works on
## a copy and returns this copy.
## **Since**: Version 1.2.
runnableExamples:
import algorithm
doAssert a.outplace(insert(10)).outplace(sort()) == sorted(aCopy)
var a = @[1, 2, 3, 4, 5, 6, 7, 8, 9]
doAssert a.dup(sort) == sorted(a)
# Chaining:
var aCopy = a
aCopy.insert(10)
doAssert a.dup(insert(10), sort) == sorted(aCopy)
var s1 = "abc"
var s2 = "xyz"
doAssert s1 & s2 == s1.dup(&= s2)
result = newNimNode(nnkStmtListExpr, arg)
let tmp = genSym(nskVar, "dupResult")
result.add newVarStmt(tmp, arg)
expectKind calls, nnkArgList
let body =
if calls.len == 1 and calls[0].kind in {nnkStmtList, nnkStmtListExpr}:
calls[0]
else:
calls
for call in body:
result.add underscoredCall(call, tmp)
result.add tmp
expectKind call, nnkCallKinds
let tmp = genSym(nskVar, "outplaceResult")
var callsons = call[0..^1]
callsons.insert(tmp, inplaceArgPosition)
result = newTree(nnkStmtListExpr,
newVarStmt(tmp, arg),
copyNimNode(call).add callsons,
tmp)
proc transLastStmt(n, res, bracketExpr: NimNode): (NimNode, NimNode, NimNode) {.since: (1, 1).} =
# Looks for the last statement of the last statement, etc...
@ -312,17 +322,17 @@ when isMainModule:
import algorithm
var a = @[1, 2, 3, 4, 5, 6, 7, 8, 9]
doAssert outplace(a, sort()) == sorted(a)
doAssert a.outplace(sort()) == sorted(a)
doAssert dup(a, sort(_)) == sorted(a)
doAssert a.dup(sort) == sorted(a)
#Chaining:
var aCopy = a
aCopy.insert(10)
doAssert a.outplace(insert(10)).outplace(sort()) == sorted(aCopy)
doAssert a.dup(insert(10)).dup(sort()) == sorted(aCopy)
import random
const b = @[0, 1, 2]
let c = b.outplace shuffle()
let c = b.dup shuffle()
doAssert c[0] == 1
doAssert c[1] == 0