public Unit VisitWhileStmt(Stmt.While stmt)
{
Resolve(stmt.Condition);
Resolve(stmt.Body);
return(new Unit());
}
/// <summary>
/// Parse a for loop
/// </summary>
/// <returns>The statement</returns>
private Stmt ForStatement()
{
_loop_depth++;
try
{
Consume(TokenType.LEFT_PAREN, "Expect '(' after 'for'.");
// Initializer
Stmt initializer;
if (Match(TokenType.SEMICOLON))
{
// No initialiser
initializer = null;
}
else if (Match(TokenType.VAR))
{
// Its a variable decalration
initializer = VarDeclaration();
}
else
{
// Its an expression
// This must be a _statement_
initializer = ExpressionStatement();
}
// Condition
Expr condition = null;
if (!Check(TokenType.SEMICOLON))
{
condition = Expression();
}
Consume(TokenType.SEMICOLON, "Expect ';' after loop condition.");
// Increment
Expr increment = null;
if (!Check(TokenType.SEMICOLON))
{
increment = Expression();
}
Consume(TokenType.RIGHT_PAREN, "Expect ')' after for clauses.");
// Body
Stmt body = Statement();
// Convert to a while loop
if (increment != null)
{
body = new Stmt.Block(new[] { body, new Stmt.ExpressionStatement(increment) });
}
if (condition == null)
{
// No condition, so set to true
condition = new Expr.Literal(true);
}
body = new Stmt.While(condition, body);
if (initializer != null)
{
body = new Stmt.Block(new[] { initializer, body });
}
return(body);
}
finally
{
_loop_depth--;
}
}
public object VisitWhileStmt(Stmt.While stmt, object options)
{
throw new NotImplementedException();
}
public object visitWhileStmt(Stmt.While stmt)
{
resolve(stmt.condition);
resolve(stmt.body);
return(null);
}
public object VisitWhileStmt(Stmt.While stmt)
{
Resolve(stmt.Condition);
Resolve(stmt.Body);
return(null);
}
private Stmt ForStatment()
{
try
{
this.LoopCounter += 1;
Consume(LEFT_PAREN, "Exepect '(' after 'for.");
Stmt initialiser;
if (Match(SEMICOLON))
{
initialiser = null;
}
else if (Match(VAR))
{
initialiser = VarDeclaration();
}
else
{
initialiser = ExpressionStatement();
}
Expr Condition = null;
if (!Check(SEMICOLON))
{
Condition = Expression();
}
Consume(SEMICOLON, "Expect ';' after loop condition.");
Expr increment = null;
if (!Check(RIGHT_PAREN))
{
increment = Expression();
}
Consume(RIGHT_PAREN, "Expect ')' after for clausess.");
Stmt body = Statement();
if (increment != null)
{
body = new Stmt.Block(new List <Stmt> {
body, new Stmt.ExpressionStmt(increment)
});
}
if (Condition == null)
{
Condition = new Expr.Literal(true);
}
body = new Stmt.While(Condition, body);
if (initialiser != null)
{
body = new Stmt.Block(new List <Stmt> {
initialiser, body
});
}
return(body);
}
finally
{
LoopCounter--;
}
}
public Stmt VisitWhileStmt(Stmt.While stmt)
{
throw new NotImplementedException();
}
private Stmt ForStatement()
{
Consume(LeftParen, "Expect '(' after 'for'.");
Stmt initializer;
if (Match(Semicolon))
{
initializer = null;
}
else if (Match(Var))
{
initializer = VarDeclaration();
}
else
{
initializer = ExpressionStatement();
}
Expr condition = null;
if (!Check(Semicolon))
{
condition = Expression();
}
Consume(Semicolon, "Expect ';' after loop condition.");
Expr increment = null;
if (!Check(RightParen))
{
increment = Expression();
}
Consume(RightParen, "Expect ')' after for clauses.");
Stmt body = Statement();
if (increment != null)
{
body = new Stmt.Block(
new List <Stmt> {
body, new Stmt.Expression(increment)
});
}
if (condition == null)
{
condition = new Expr.Literal(true);
}
body = new Stmt.While(condition, body);
if (initializer != null)
{
body = new Stmt.Block(new List <Stmt> {
initializer, body
});
}
return(body);
}
public object VisitWhileStmt(Stmt.While stmt, object options = null)
{
return(null);
}
private Stmt ForStatement()
{
// The "for" implementation is a bit special in that it doesn't use any special AST nodes of its own.
// Instead, it just desugars the for loop into already existing elements in our toolbox.
// More details: http://craftinginterpreters.com/control-flow.html#desugaring
Consume(LEFT_PAREN, "Expect '(' after 'for'.");
Stmt initializer;
if (Match(SEMICOLON))
{
initializer = null;
}
else if (Match(VAR))
{
initializer = VarDeclaration();
}
else
{
initializer = ExpressionStatement();
}
Expr condition = null;
if (!Check(SEMICOLON))
{
condition = Expression();
}
Consume(SEMICOLON, "Expect ';' after loop condition.");
Expr increment = null;
if (!Check(RIGHT_PAREN))
{
increment = Expression();
}
Consume(RIGHT_PAREN, "Expect ')' after for clauses.");
Stmt body = Statement();
if (increment != null)
{
body = new Stmt.Block(new List <Stmt>
{
body,
new Stmt.ExpressionStmt(increment)
});
}
condition ??= new Expr.Literal(true);
body = new Stmt.While(condition, body);
if (initializer != null)
{
body = new Stmt.Block(new List <Stmt> {
initializer, body
});
}
return(body);
}
public string VisitWhileStmt(Stmt.While stmt)
{
return(Parenthesize2("while", stmt.Condition, stmt.Body));
}
private Stmt ForStatement()
{
Consume(LEFT_PAREN, "Expected \"(\" after \"for\".");
Stmt initializer;
if (Match(SEMICOLON))
{
initializer = null;
}
else if (Match(VAR))
{
initializer = VarDeclaration();
}
else
{
initializer = ExpressionStatement();
}
Expr condition = null;
if (!Check(SEMICOLON))
{
condition = Expression();
}
Consume(SEMICOLON, "Expected \";\" after loop condition");
Expr increment = null;
if (!Check(RIGHT_PAREN))
{
increment = Expression();
}
Consume(RIGHT_PAREN, "Expected \")\" after clauses");
Stmt body = Statement();
if (increment != null)
{
body = new Stmt.Block(new List <Stmt>()
{
body, new Stmt.Expression(increment)
});
}
if (condition == null)
{
condition = new Expr.Literal(true);
}
body = new Stmt.While(condition, body);
if (initializer != null)
{
body = new Stmt.Block(new List <Stmt>()
{
initializer, body
});
}
return(body);
}
