Add call to parser

src/parser/Parser.java

@@ -1,6 +1,7 @@
 package parser;
 
 import expression.*;
+import expression.Identifier;
 import expression.Int;
 import program.*;
 
@@ -51,12 +52,25 @@ public class Parser {
                 statement = conditional();
             } catch (SyntaxException se2) {
                 position = start;
-                statement = loop();
+                try {
+                    statement = loop();
+                } catch (SyntaxException se3) {
+                    position = start;
+                    statement = call();
+                }
             }
         }
         return statement;
     }
 
+    Program call() {
+        Identifier name = identifier();
+        consume("(");
+        Expression argument = expression();
+        consume(")");
+        return new Call(name, argument);
+    }
+
     Program loop() {
         consume("while");
         consume("(");

src/program/Call.java

@@ -0,0 +1,38 @@
+package program;
+
+import expression.Expression;
+import expression.Identifier;
+
+public class Call extends Program {
+    final Identifier name;
+    final Expression argument;
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        Call that = (Call) o;
+
+        if (!name.equals(that.name)) return false;
+        return argument.equals(that.argument);
+
+    }
+
+    @Override
+    public String toString() {
+        return name + "(" + argument + ")";
+    }
+
+    @Override
+    public int hashCode() {
+        int result = name.hashCode();
+        result = 31 * result + argument.hashCode();
+        return result;
+    }
+
+    public Call(Identifier name, Expression argument) {
+        this.name = name;
+        this.argument = argument;
+    }
+}

test/parser/ParserTest.java

@@ -52,6 +52,15 @@ public class ParserTest {
         assertEquals(loop, parser.statement());
     }
 
+    final String callCode = "print(x + 36)";
+    final Call call = new Call(new Identifier("print"), new Addition(new Identifier("x"), new Int(36)));
+
+    @Test
+    public void testStatementCall() {
+        Parser parser = new Parser(callCode);
+        assertEquals(call, parser.statement());
+    }
+
     @Test
     public void testAssignment() {
         Parser parser = new Parser(assignmentCode);
@@ -70,6 +79,12 @@ public class ParserTest {
         assertEquals(loop, parser.loop());
     }
 
+    @Test
+    public void testCall() {
+        Parser parser = new Parser(callCode);
+        assertEquals(call, parser.call());
+    }
+
     final String expressionCode = "a+b - (c - 56) + -47";
     final Expression expression = new Addition(new Subtraction(new Addition(new Identifier("a"), new Identifier("b")), new Subtraction(new Identifier("c"), new Int(56))), new Int(-47));