put the calculator to work. Here is what using the calculator from a C#
The development of the Nitra parser begins with creating a syntax module. The syntax module is a translation and encapsulation unit. The complete parser is composed of one or more syntax modules.
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After you add the AST methods, you can put the calculator to work. Here is what using the calculator from a C# application looks like:
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using N2;
using System;
class Program
{
static void Main()
{
var parserHost = new ParserHost();
for(;;)
{
Console.Write("input>");
var input = Console.ReadLine();
// Exit if user inputs empty string
if (string.IsNullOrWhiteSpace(input))
return;
// Parse the string with the starting rule
var parseResult = Calc.Start(SourceSnapshot(input), parserHost);
// Create materialized AST
var ast = CalcAstWalkers.Start(parseResult);
Console.WriteLine("Pretty print: " + ast);
// If any errors occurred, output error messages
foreach(var error in parseResult.GetErrors())
{
var lineCol = error.Location.StartLineColumn;
Console.WriteLine("(" + lineCol.Line + "," + lineCol.Column + "): " + error.Message);
}
// Calculate the expression value using AST method and output value to console
Console.WriteLine("Result: " + ast.Value());
}
}
}
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