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authorBenjamin Shirley-Quirk2020-08-05 00:44:55 +0000
committerBenjamin Shirley-Quirk2020-08-05 00:44:55 +0000
commitcb63408d7d9de91020a7a815216b531fdf944b47 (patch)
treeb983f9179a37f3f088f7b1e9230c9d705f55a947 /src/listcomp.nim
parent22799b2e439d6b74ca648060faa1e3f1ee13f946 (diff)
removed listcomp.nim
Diffstat (limited to 'src/listcomp.nim')
-rw-r--r--src/listcomp.nim69
1 files changed, 0 insertions, 69 deletions
diff --git a/src/listcomp.nim b/src/listcomp.nim
deleted file mode 100644
index c9f8dc0..0000000
--- a/src/listcomp.nim
+++ /dev/null
@@ -1,69 +0,0 @@
-import macros
-
-type ListComprehension = object
-var lc* : ListComprehension
-
-template `|`*(lc: ListComprehension, comp: untyped): untyped = lc
-
-macro `[]`*(lc: ListComprehension, comp, typ: untyped): untyped =
- ## List comprehension, returns a sequence. `comp` is the actual list
- ## comprehension, for example ``x | (x <- 1..10, x mod 2 == 0)``. `typ` is
- ## the type that will be stored inside the result seq.
- ##
- ## .. code-block:: nim
- ##
- ## echo lc[x | (x <- 1..10, x mod 2 == 0), int]
- ##
- ## const n = 20
- ## echo lc[(x,y,z) | (x <- 1..n, y <- x..n, z <- y..n, x*x + y*y == z*z),
- ## tuple[a,b,c: int]]
-
- expectLen(comp, 3)
- expectKind(comp, nnkInfix)
- assert($comp[0] == "|")
-
- result = newCall(
- newDotExpr(
- newIdentNode("result"),
- newIdentNode("add")),
- comp[1])
-
- for i in countdown(comp[2].len-1, 0):
- let x = comp[2][i]
- expectMinLen(x, 1)
- if x[0].kind == nnkIdent and x[0].strVal == "<-":
- expectLen(x, 3)
- result = newNimNode(nnkForStmt).add(x[1], x[2], result)
- else:
- result = newIfStmt((x, result))
-
- result = newNimNode(nnkCall).add(
- newNimNode(nnkPar).add(
- newNimNode(nnkLambda).add(
- newEmptyNode(),
- newEmptyNode(),
- newEmptyNode(),
- newNimNode(nnkFormalParams).add(
- newNimNode(nnkBracketExpr).add(
- newIdentNode("seq"),
- typ)),
- newEmptyNode(),
- newEmptyNode(),
- newStmtList(
- newAssignment(
- newIdentNode("result"),
- newNimNode(nnkPrefix).add(
- newIdentNode("@"),
- newNimNode(nnkBracket))),
- result))))
-
-
-when isMainModule:
- var a = lc[x | (x <- 1..10, x mod 2 == 0), int]
- assert a == @[2, 4, 6, 8, 10]
-
- const n = 20
- var b = lc[(x,y,z) | (x <- 1..n, y <- x..n, z <- y..n, x*x + y*y == z*z),
- tuple[a,b,c: int]]
- assert b == @[(a: 3, b: 4, c: 5), (a: 5, b: 12, c: 13), (a: 6, b: 8, c: 10),
-(a: 8, b: 15, c: 17), (a: 9, b: 12, c: 15), (a: 12, b: 16, c: 20)]