public static object Evaluate(string expression)
{
var ast = ArmExpressionParser.Parse(expression);
var value = ArmExpressionEvaluator.Evaluate(ast);
return(value);
}
public static ArmExpressionAst Parse(string armExpression)
{
var lexer = ArmExpressionLexer.Create();
var tokens = lexer.Lex(armExpression);
var ast = ArmExpressionParser.Parse(tokens);
return(ast);
}
public static ArmExpressionAst ParseArmExpressionAst(TokenStream stream)
{
var peek = stream.Peek();
return(peek switch
{
OpenParenToken _ => ArmExpressionParser.ParseArmSubexpressionAst(stream),
IdentifierToken _ => ArmExpressionParser.ParseDottedNotationExpressionAst(stream),
StringLiteralToken _ => ArmExpressionParser.ParseArmStringLiteralExpressionAst(stream),
IntegerToken _ => ArmExpressionParser.ParseArmNumericLiteralExpressionAst(stream),
_ => throw new InvalidOperationException(),
});
public static ArmExpressionAst Parse(IEnumerable <SyntaxToken> lexerTokens)
{
// remove all whitespace
var tokens = lexerTokens.Where(lt => !(lt is WhitespaceToken));
var stream = new TokenStream(tokens);
var program = ArmExpressionParser.ParseArmExpressionAst(stream);
if (!stream.Eof)
{
throw new InvalidOperationException("End of expression expected.");
}
return(program);
}