Split interpreter values from primitives

1 files changed, 41 insertions, 0 deletions

diff --git a/src/main/java/org/zwobble/couscous/interpreter/values/StringInterpreterValue.java b/src/main/java/org/zwobble/couscous/interpreter/values/StringInterpreterValue.java
new file mode 100644
index 0000000..f17cdd5
--- /dev/null
+++ b/src/main/java/org/zwobble/couscous/interpreter/values/StringInterpreterValue.java
@@ -0,0 +1,41 @@
+package org.zwobble.couscous.interpreter.values;
+
+import java.util.Optional;
+
+import org.zwobble.couscous.values.IntegerValue;
+import org.zwobble.couscous.values.PrimitiveValue;
+import org.zwobble.couscous.values.PrimitiveValues;
+import org.zwobble.couscous.values.StringValue;
+
+import static java.util.Arrays.asList;
+
+import lombok.Value;
+import lombok.val;
+
+@Value
+public class StringInterpreterValue implements InterpreterValue {
+    public static final ConcreteType<?> TYPE = ConcreteType.<StringInterpreterValue>builder(StringValue.REF)
+        .method("length", asList(),
+            (receiver, arguments) -> new IntegerInterpreterValue(receiver.value.length()))
+        
+        .method("substring", asList(IntegerValue.REF, IntegerValue.REF),
+            (receiver, arguments) -> {
+                val startIndex = (IntegerInterpreterValue)arguments.get(0);
+                val endIndex = (IntegerInterpreterValue)arguments.get(1);
+                return new StringInterpreterValue(receiver.value.substring(startIndex.getValue(), endIndex.getValue()));
+            })
+        
+        .build();
+    
+    String value;
+
+    @Override
+    public ConcreteType<?> getType() {
+        return TYPE;
+    }
+
+    @Override
+    public Optional<PrimitiveValue> toPrimitiveValue() {
+        return Optional.of(PrimitiveValues.value(value));
+    }
+}