public void TestSetRollbackPoint()
{
Tokens tokens = new Tokens();
tokens.AddTokens ( new string[] { "1", "2", "3", "4", "5" } );
Assert.AreEqual ( "1", tokens.PeekToken () );
tokens.SetMark ();
Assert.AreEqual ( "1", tokens.PullToken () );
Assert.AreEqual ( "2", tokens.PullToken () );
Assert.AreEqual ( "3", tokens.PullToken () );
tokens.RollbackToMark ();
Assert.AreEqual ( "1", tokens.PeekToken () );
}
public bool TryParse(Tokens tokens, IScope scope, out IStatement statement)
{
// This is a block call
Variable variable = new Variable ( _executorFactory.GetVariableExecutor() );
variable.Scope = scope;
variable.Ident = tokens.PullToken ();
// Check if there is an indexer into the variable
if (tokens.PeekToken () == "[")
{
tokens.PullToken ();
variable.Indexer = _expressionParser.ParseExpression ( scope, tokens );
tokens.RemoveNextToken ("]");
}
if ( tokens.NextTokenIs("(") )
{
// Parse the parameters..
variable.Parameters = _expressionParser.ParseArray( scope, tokens ) as ArrayExpr;
}
statement = variable;
return true;
}
/// <summary>
/// Value is a constant string, number or variable name.
/// </summary>
/// <param name="tokens"></param>
/// <returns></returns>
public Expression ParseValue( IScope scope, Tokens tokens )
{
Expression value = null;
if ( tokens.NextTokenIs ( BeginBlock ) )
{
value = _blockParser.GetBlock ( scope, tokens );
}
else if ( tokens.PeekToken().StartsWith ( "'" ) && tokens.PeekToken().EndsWith ( "'" ) )
{
string literal = tokens.PullToken().Trim ( '\'' );
value = new StringLiteral
{
Value = literal
};
}
else if ( tokens.PeekToken().IsNumber () )
{
value = new NumberLiteral
{
Value = double.Parse ( tokens.PullToken() )
};
}
else if ( tokens.NextTokenIs(BeginArray) )
{
return this.ParseArray ( scope, tokens );
}
else
{
var variable = new Variable ( _executorFactory.GetVariableExecutor () );
variable.Scope = scope;
variable.Ident = tokens.PullToken();
// Check if there is an indexer into the variable
if (tokens.PeekToken () == "[")
{
tokens.PullToken ();
variable.Indexer = ParseExpression ( scope, tokens );
tokens.RemoveNextToken ("]");
}
value = variable;
}
return value;
}