Add var declarations parser. Also, Happy 22nd Birthday to me!! #CSisLife

Project3Java/src/csc426/ast/Block.java

@@ -3,22 +3,22 @@
 public class Block {
 
  private ValDecls valDecls;
-// private VarDecls varDecls;
+ private VarDecls varDecls;
 // private FunDecls funDecls;
 // private Stmt stmt;
 
 // public Block(ValDecls valDecls, VarDecls varDecls, FunDecls funDecls, Stmt stmt) {
- public Block(ValDecls valDecls) {
+ public Block(ValDecls valDecls, VarDecls varDecls) {
  this.valDecls = valDecls;
-// this.varDecls = varDecls;
+ this.varDecls = varDecls;
 // this.funDecls = funDecls;
 // this.stmt = stmt;
  }
 
  public void display(String indentation) {
  System.out.println(indentation + "Block");
  valDecls.display(indentation + " ");
-// varDecls.display(indentation + " ");
+ varDecls.display(indentation + " ");
 // funDecls.display(indentation + " ");
 // stmt.display(indentation + " ");
  }

Project3Java/src/csc426/ast/Type.java

@@ -1,5 +1,23 @@
 package csc426.ast;
 
+import csc426.syntax.TokenType;
+
 public class Type {
+
+ private TokenType tokenType;
+
+ public Type(TokenType tokenType) {
+ this.tokenType = tokenType;
+ }
+
+ public String toString() {
+ if (tokenType == TokenType.INT)
+ return "Int";
+ else if (tokenType == TokenType.BOOL) 
+ return "Bool";
+ else if (tokenType == TokenType.VOID)
+ return "Void";
+ return "";
+ }
 
 }

Project3Java/src/csc426/ast/VarDecl.java

@@ -2,4 +2,15 @@
 
 public class VarDecl {
 
+ private String id;
+ private Type type;
+
+ public VarDecl(String id, Type type) {
+ this.id = id;
+ this.type = type;
+ }
+
+ public void display(String indentation) {
+ System.out.println(indentation + "Var " + id + " : " + type);
+ }
 }

Project3Java/src/csc426/ast/VarDecls.java

@@ -1,10 +1,19 @@
 package csc426.ast;
 
+import java.util.List;
+
 public class VarDecls {
+
+ private List<VarDecl> vars;
 
- public void display(String indentation) {
- // TODO Auto-generated method stub
-
+ public VarDecls(List<VarDecl> vars) {
+ this.vars = vars;
  }
 
+ public void display(String indentation) {
+ for (VarDecl var : vars) {
+ var.display(indentation + " ");
+ }
+ }
+
 }

Project3Java/src/csc426/syntax/Parser.java

@@ -60,26 +60,25 @@ public Program parseProgram() {
  }
 
  /*
- * <Block> --> <ValDecls>    FIRST = VAL
+ * <Block> --> <ValDecls> <VarDecls> <FunDecls> <Stmt> FIRST = VAL, VAR, FUN, FIRST(Stmt)
  */
  public Block parseBlock() {
  ValDecls vs = parseValDecls();
- return new Block(vs);
+ VarDecls rs = parseVarDecls();
+
+ return new Block(vs, rs);
  }
 
  /*
  * <ValDecls> --> <ValDecl> <ValDecls> FIRST = VAL
  * | ε FOLLOW = VAR
  */
  public ValDecls parseValDecls() {
- if (check(TokenType.VAL)) {
- List<ValDecl> vdList = new ArrayList<ValDecl>();
- while (check(TokenType.VAL)) {
- vdList.add(parseValDecl());
- }
- return new ValDecls(vdList);
+ List<ValDecl> vdList = new ArrayList<ValDecl>();
+ while (check(TokenType.VAL)) {
+ vdList.add(parseValDecl());
  }
- return new ValDecls(new ArrayList<ValDecl>());
+ return new ValDecls(vdList);
  }
 
  /*
@@ -107,6 +106,50 @@ public int parseSign() {
  }
  return 1;
  }
+
+ /*
+ * <VarDecls> --> <VarDecl> <VarDecls> FIRST = VAR
+ * | ε FOLLOW = FUN, FIRST(Stmt)
+ */
+ public VarDecls parseVarDecls() {
+ List<VarDecl> vrList = new ArrayList<VarDecl>();
+ while (check(TokenType.VAR)) {
+ vrList.add(parseVarDecl());
+ }
+ return new VarDecls(vrList);
+ }
+
+ /*
+ * <VarDecl> --> var id : <Type> ; FIRST = VAR
+ */
+ public VarDecl parseVarDecl() {
+ match(TokenType.VAR);
+ Token id = match(TokenType.ID);
+ match(TokenType.COLON);
+ Type type = parseType();
+ match(TokenType.SEMI);
+ return new VarDecl(id.lexeme, type);
+ }
+
+ // Better implementation? Too much redundant code
+ public Type parseType() {
+
+ if (check(TokenType.INT)) {
+ match(TokenType.INT);
+ return new Type(TokenType.INT);
+ } else if (check(TokenType.BOOL)) {
+ match(TokenType.BOOL);
+ return new Type(TokenType.BOOL);
+ } else if (check(TokenType.VOID)) {
+ match(TokenType.VOID);
+ return new Type(TokenType.VOID);
+ } else {
+ System.err.println("Invalid var type: Var type has to be INT, BOOL, or VOID");
+ System.exit(1);
+ }
+
+ return null; // Unreachable
+ }
 
  private Scanner scanner;
  private Token current;