Create if-else statement evaluator

smnp/runtime/evaluators/condition.py

@@ -0,0 +1,35 @@
+from smnp.error.runtime import RuntimeException
+from smnp.runtime.evaluator import Evaluator, evaluate
+from smnp.runtime.evaluators.expression import expressionEvaluator
+from smnp.type.model import Type
+
+
+class IfElseEvaluator(Evaluator):
+
+    @classmethod
+    def evaluator(cls, node, environment):
+        condition = expressionEvaluator(doAssert=True)(node.condition, environment).value
+
+        if condition.type != Type.BOOL:
+            raise RuntimeException(f"Only {Type.BOOL.name.lower()} types can be used as conditions in conditional expression", node.condition.pos)
+
+        if condition.value:
+            return expressionEvaluator(doAssert=True)(node.ifNode, environment).value
+        else:
+            return expressionEvaluator(doAssert=True)(node.elseNode, environment).value
+
+
+class IfElseStatementEvaluator(Evaluator):
+
+    @classmethod
+    def evaluator(cls, node, environment):
+        condition = expressionEvaluator(doAssert=True)(node.condition, environment).value
+
+        if condition.type != Type.BOOL:
+            raise RuntimeException(
+                f"Only {Type.BOOL.name.lower()} types can be used as conditions in conditional expression", node.condition.pos)
+
+        if condition.value:
+            evaluate(node.ifNode, environment)
+        else:
+            evaluate(node.elseNode, environment)

smnp/runtime/evaluators/expression.py

@@ -1,3 +1,4 @@
+from smnp.ast.node.condition import IfElse
 from smnp.ast.node.expression import Sum, Relation
 from smnp.ast.node.factor import NotOperator, Power, Loop
 from smnp.ast.node.identifier import FunctionCall, Assignment
@@ -22,6 +23,7 @@ def expressionEvaluator(doAssert=False):
 
         from smnp.runtime.evaluators.sum import SumEvaluator
         from smnp.runtime.evaluators.relation import RelationEvaluator
+        from smnp.runtime.evaluators.condition import IfElseEvaluator
         result = Evaluator.oneOf(
             Evaluator.forNodes(FunctionCallEvaluator.evaluate, FunctionCall),
             Evaluator.forNodes(MinusEvaluator.evaluate, MinusOperator),
@@ -33,6 +35,7 @@ def expressionEvaluator(doAssert=False):
             Evaluator.forNodes(ProductEvaluator.evaluate, Product),
             Evaluator.forNodes(SumEvaluator.evaluate, Sum),
             Evaluator.forNodes(RelationEvaluator.evaluate, Relation),
+            Evaluator.forNodes(IfElseEvaluator.evaluate, IfElse),
             AtomEvaluator.evaluate
         )(node, environment)