Added basic support for arrays

1 files changed, 40 insertions, 12 deletions

diff --git a/src/Compiler/Parser.java b/src/Compiler/Parser.java
index d0556e4..eba3513 100644
--- a/src/Compiler/Parser.java
+++ b/src/Compiler/Parser.java
@@ -3,7 +3,6 @@ package Compiler;
 import java.util.ArrayList;
 import java.util.List;
 
-import Compiler.Statement.BlockStatement;
 
 public class Parser {
     private final List<Token> tokens;
@@ -44,11 +43,17 @@ public class Parser {
     //Clean up and reduce code mess
     private Statement declaration(){
         if (matchAndAdvance(TokenType.INT)){
+            if(matchAndAdvance(TokenType.DIMENSION)){
+                return arrayDeclaration("int");
+            }
             matchOrError(TokenType.DEFINE, ":: Required for variable definition");
             matchOrError(TokenType.IDENTIFIER,"Expected variable name.");
             Token varName = getPreviousToken();
             return new Statement.VariableDeclaration(varName,"int");
         } else if (matchAndAdvance(TokenType.REAL)){
+            if(matchAndAdvance(TokenType.DIMENSION)){
+                return arrayDeclaration("real");
+            }
             matchOrError(TokenType.DEFINE, ":: Required for variable definition");
             matchOrError(TokenType.IDENTIFIER,"Expected variable name.");
             Token varName = getPreviousToken();
@@ -79,7 +84,23 @@ public class Parser {
         return null;
     }
 
-    private BlockStatement blockStatement(){
+    private Statement arrayDeclaration(String type){
+        matchOrError(TokenType.LEFT_PAREN,"Expected ')'");
+        List<Expression> dimensions = new ArrayList<>();
+        Expression dimension = expression();
+        dimensions.add(dimension);
+        while(matchAndAdvance(TokenType.COMMA)){
+            dimension = expression();
+            dimensions.add(dimension);
+        }
+        matchOrError(TokenType.RIGHT_PAREN, "Expected ')'");
+        matchOrError(TokenType.DEFINE, ":: Required for variable definition");
+        matchOrError(TokenType.IDENTIFIER,"Expected variable name.");
+        Token varName = getPreviousToken();
+        return new Statement.ArrayDeclaration(varName, type, dimensions);
+    }
+
+    private Statement blockStatement(){
         List<Statement> statements = new ArrayList<>();
         while(!matchAndAdvance(TokenType.END)&&!checkToken(TokenType.ELSE)){
             if(checkEOF()){
@@ -107,8 +128,8 @@ public class Parser {
     private Statement ifStatement(){
         Expression condition = expression();
         if(matchOrError(TokenType.THEN, "then expected after if statement")){
-            Statement.BlockStatement ifBlock = blockStatement();
-            Statement.BlockStatement elseBlock=null;
+            Statement ifBlock = blockStatement();
+            Statement elseBlock=null;
             
             if(matchAndAdvance(TokenType.ELSE)){
                 elseBlock=blockStatement();
@@ -133,7 +154,7 @@ public class Parser {
         if(matchAndAdvance(TokenType.COMMA)){
            step = expression();
         }
-        Statement.BlockStatement codeBlock = blockStatement();
+        Statement codeBlock = blockStatement();
         matchOrError(TokenType.DO, "Do statements end with do");
         return new Statement.DoStatement(variable, start, stop, step,codeBlock);
 
@@ -143,7 +164,7 @@ public class Parser {
         matchOrError(TokenType.LEFT_PAREN, " missing '(' for do statement condition");
         Expression condition = expression();
         matchOrError(TokenType.RIGHT_PAREN, " missing ')' for do  condition");
-        Statement.BlockStatement codeBlock = blockStatement();
+        Statement codeBlock = blockStatement();
         matchOrError(TokenType.DO, "Do while statements end with do");
         return new Statement.DoWhileStatement(condition,codeBlock);
     }
@@ -157,11 +178,7 @@ public class Parser {
         Expression variable = expression();
         if (matchAndAdvance(TokenType.EQUALS)){
             Expression assignedvalue = expression();
-
-            if (variable instanceof Expression.Variable){
-                return new Expression.AssignmentExpression(((Expression.Variable)variable).name,assignedvalue);
-            }
-            throw error(getCurrentToken(),"Left of assignment must be a variable");
+            return new Expression.AssignmentExpression(variable,assignedvalue);
         }
         return variable;
     }
@@ -240,7 +257,18 @@ public class Parser {
         }
 
         if (matchAndAdvance(TokenType.IDENTIFIER)) {
-
+            Token name= getPreviousToken();
+            if(matchAndAdvance(TokenType.LEFT_PAREN)){
+                List<Expression> positions = new ArrayList<>();
+                Expression position = expression();
+                positions.add(position);
+                while(matchAndAdvance(TokenType.COMMA)){
+                    position = expression();
+                    positions.add(position);
+                }
+                matchOrError(TokenType.RIGHT_PAREN,"Expected ')'");
+                return new Expression.ArrayVariable(name, positions);
+            }
             return new Expression.Variable(getPreviousToken());
           }