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59 lines
1.0 KiB
Nim
59 lines
1.0 KiB
Nim
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template withOpenFile(f: expr, filename: string, mode: TFileMode,
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actions: stmt): stmt {.immediate.} =
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block:
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# test that 'f' is implicitly 'injecting':
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var f: TFile
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if open(f, filename, mode):
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try:
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actions
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finally:
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close(f)
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else:
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quit("cannot open for writing: " & filename)
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withOpenFile(txt, "ttempl3.txt", fmWrite):
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writeln(txt, "line 1")
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txt.writeln("line 2")
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var
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myVar: array[0..1, int]
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# Test zero argument template:
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template ha: expr = myVar[0]
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ha = 1
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echo(ha)
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# Test identifier generation:
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template prefix(name: expr): expr {.immediate.} = `"hu" name`
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var `hu "XYZ"` = "yay"
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echo prefix(XYZ)
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template typedef(name: expr, typ: typeDesc) {.immediate, dirty.} =
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type
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`T name`* = typ
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`P name`* = ref `T name`
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typedef(myint, int)
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var x: PMyInt
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# Test UFCS
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type
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Foo = object
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arg: int
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proc initFoo(arg: int): Foo =
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result.arg = arg
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template create(typ: typeDesc, arg: expr): expr = `init typ`(arg)
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var ff = Foo.create(12)
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echo ff.arg
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