Add support for custom functions

smnp/newast/node/function.py

@@ -0,0 +1,67 @@
+from smnp.newast.node.block import BlockNode
+from smnp.newast.node.identifier import IdentifierNode
+from smnp.newast.node.iterable import abstractIterableParser
+from smnp.newast.node.model import Node
+from smnp.newast.node.none import NoneNode
+from smnp.newast.node.statement import StatementNode
+from smnp.newast.node.variable import TypedVariableNode
+from smnp.newast.parser import Parser
+from smnp.token.type import TokenType
+
+
+class ArgumentsDeclarationNode(Node):
+
+    @classmethod
+    def _parse(cls, input):
+        raise RuntimeError("This class is not supposed to be automatically called")
+
+
+class FunctionDefinition(StatementNode):
+    def __init__(self, pos):
+        super().__init__(pos)
+        self.children = [NoneNode(), NoneNode(), NoneNode()]
+
+    @property
+    def name(self):
+        return self[0]
+
+    @name.setter
+    def name(self, value):
+        self[0] = value
+
+    @property
+    def arguments(self):
+        return self[1]
+
+    @arguments.setter
+    def arguments(self, value):
+        self[1] = value
+
+    @property
+    def body(self):
+        return self[2]
+
+    @body.setter
+    def body(self, value):
+        self[2] = value
+
+    @classmethod
+    def _parse(cls, input):
+        def createNode(function, name, arguments, body):
+            node = FunctionDefinition(function.pos)
+            node.name = name
+            node.arguments = arguments
+            node.body = body
+            return node
+
+        return Parser.allOf(
+            Parser.terminalParser(TokenType.FUNCTION),
+            IdentifierNode.identifierParser(),
+            cls._argumentsDeclarationParser(),
+            BlockNode.parse,
+            createNode=createNode
+        )(input)
+
+    @staticmethod
+    def _argumentsDeclarationParser():
+        return abstractIterableParser(ArgumentsDeclarationNode, TokenType.OPEN_PAREN, TokenType.CLOSE_PAREN, TypedVariableNode.parser())