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authorAraq <rumpf_a@web.de>2017-03-09 14:58:14 +0100
committerAraq <rumpf_a@web.de>2017-03-09 14:58:14 +0100
commit475579541621ca83cfcbb35df7f5d9ef4236cdfa (patch)
tree81f95f9ae846b61c7f2878a275413f5a3fc9bea3 /nimsuggest/tests/twithin_macro.nim
parentda821a22d9e390d59f66018630fb4c39ba83eaf3 (diff)
downloadNim-475579541621ca83cfcbb35df7f5d9ef4236cdfa.tar.gz
nimsuggest: more precise cursor tracking
Diffstat (limited to 'nimsuggest/tests/twithin_macro.nim')
-rw-r--r--nimsuggest/tests/twithin_macro.nim213
1 files changed, 213 insertions, 0 deletions
diff --git a/nimsuggest/tests/twithin_macro.nim b/nimsuggest/tests/twithin_macro.nim
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+++ b/nimsuggest/tests/twithin_macro.nim
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+
+import macros
+
+macro class*(head, body: untyped): untyped =
+  # The macro is immediate, since all its parameters are untyped.
+  # This means, it doesn't resolve identifiers passed to it.
+
+  var typeName, baseName: NimNode
+
+  # flag if object should be exported
+  var exported: bool
+
+  if head.kind == nnkInfix and head[0].ident == !"of":
+    # `head` is expression `typeName of baseClass`
+    # echo head.treeRepr
+    # --------------------
+    # Infix
+    #   Ident !"of"
+    #   Ident !"Animal"
+    #   Ident !"RootObj"
+    typeName = head[1]
+    baseName = head[2]
+
+  elif head.kind == nnkInfix and head[0].ident == !"*" and
+       head[2].kind == nnkPrefix and head[2][0].ident == !"of":
+    # `head` is expression `typeName* of baseClass`
+    # echo head.treeRepr
+    # --------------------
+    # Infix
+    #   Ident !"*"
+    #   Ident !"Animal"
+    #   Prefix
+    #     Ident !"of"
+    #     Ident !"RootObj"
+    typeName = head[1]
+    baseName = head[2][1]
+    exported = true
+
+  else:
+    quit "Invalid node: " & head.lispRepr
+
+  # The following prints out the AST structure:
+  #
+  # import macros
+  # dumptree:
+  #   type X = ref object of Y
+  #     z: int
+  # --------------------
+  # StmtList
+  #   TypeSection
+  #     TypeDef
+  #       Ident !"X"
+  #       Empty
+  #       RefTy
+  #         ObjectTy
+  #           Empty
+  #           OfInherit
+  #             Ident !"Y"
+  #           RecList
+  #             IdentDefs
+  #               Ident !"z"
+  #               Ident !"int"
+  #               Empty
+
+  # create a type section in the result
+  result =
+    if exported:
+      # mark `typeName` with an asterisk
+      quote do:
+        type `typeName`* = ref object of `baseName`
+    else:
+      quote do:
+        type `typeName` = ref object of `baseName`
+
+  # echo treeRepr(body)
+  # --------------------
+  # StmtList
+  #   VarSection
+  #     IdentDefs
+  #       Ident !"name"
+  #       Ident !"string"
+  #       Empty
+  #     IdentDefs
+  #       Ident !"age"
+  #       Ident !"int"
+  #       Empty
+  #   MethodDef
+  #     Ident !"vocalize"
+  #     Empty
+  #     Empty
+  #     FormalParams
+  #       Ident !"string"
+  #     Empty
+  #     Empty
+  #     StmtList
+  #       StrLit ...
+  #   MethodDef
+  #     Ident !"age_human_yrs"
+  #     Empty
+  #     Empty
+  #     FormalParams
+  #       Ident !"int"
+  #     Empty
+  #     Empty
+  #     StmtList
+  #       DotExpr
+  #         Ident !"this"
+  #         Ident !"age"
+
+  # var declarations will be turned into object fields
+  var recList = newNimNode(nnkRecList)
+
+  # expected name of constructor
+  let ctorName = newIdentNode("new" & $typeName)
+
+  # Iterate over the statements, adding `this: T`
+  # to the parameters of functions, unless the
+  # function is a constructor
+  for node in body.children:
+    case node.kind:
+
+      of nnkMethodDef, nnkProcDef:
+        # check if it is the ctor proc
+        if node.name.kind != nnkAccQuoted and node.name.basename == ctorName:
+          # specify the return type of the ctor proc
+          node.params[0] = typeName
+        else:
+          # inject `self: T` into the arguments
+          node.params.insert(1, newIdentDefs(ident("self"), typeName))
+        result.add(node)
+
+      of nnkVarSection:
+        # variables get turned into fields of the type.
+        for n in node.children:
+          recList.add(n)
+
+      else:
+        result.add(node)
+
+  # Inspect the tree structure:
+  #
+  # echo result.treeRepr
+  # --------------------
+  # StmtList
+  #   TypeSection
+  #     TypeDef
+  #       Ident !"Animal"
+  #       Empty
+  #       RefTy
+  #         ObjectTy
+  #           Empty
+  #           OfInherit
+  #             Ident !"RootObj"
+  #           Empty   <= We want to replace this
+  # MethodDef
+  # ...
+
+  result[0][0][2][0][2] = recList
+
+  # Lets inspect the human-readable version of the output
+  #echo repr(result)
+
+# ---
+
+class Animal of RootObj:
+  var name: string
+  var age: int
+  method vocalize: string {.base.} = "..." # use `base` pragma to annonate base methods
+  method age_human_yrs: int {.base.} = self.age # `this` is injected
+  proc `$`: string = "animal:" & self.name & ":" & $self.age
+
+class Dog of Animal:
+  method vocalize: string = "woof"
+  method age_human_yrs: int = self.age * 7
+  proc `$`: string = "dog:" & self.name & ":" & $self.age
+
+class Cat of Animal:
+  method vocalize: string = "meow"
+  proc `$`: string = "cat:" & self.name & ":" & $self.age
+
+class Rabbit of Animal:
+  proc newRabbit(name: string, age: int) = # the constructor doesn't need a return type
+    result = Rabbit(name: name, age: age)
+  method vocalize: string = "meep"
+  proc `$`: string =
+    self.#[!]#
+    result = "rabbit:" & self.name & ":" & $self.age
+
+# ---
+
+var animals: seq[Animal] = @[]
+animals.add(Dog(name: "Sparky", age: 10))
+animals.add(Cat(name: "Mitten", age: 10))
+
+for a in animals:
+  echo a.vocalize()
+  echo a.age_human_yrs()
+
+let r = newRabbit("Fluffy", 3)
+echo r.vocalize()
+echo r.age_human_yrs()
+echo r
+
+discard """
+$nimsuggest --tester $file
+>sug $1
+sug;;skField;;age;;int;;$file;;167;;6;;"";;100;;None
+sug;;skField;;name;;string;;$file;;166;;6;;"";;100;;None
+sug;;skMethod;;twithin_macro.age_human_yrs;;proc (self: Animal): int;;$file;;169;;9;;"";;100;;None
+sug;;skMethod;;twithin_macro.vocalize;;proc (self: Animal): string;;$file;;168;;9;;"";;100;;None
+sug;;skMethod;;twithin_macro.vocalize;;proc (self: Rabbit): string;;$file;;184;;9;;"";;100;;None
+sug;;skMacro;;twithin_macro.class;;proc (head: untyped, body: untyped): untyped{.gcsafe, locks: <unknown>.};;$file;;4;;6;;"";;50;;None*
+"""