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#include "mpParser.h"
void Calc()
{
char line[100];
try
{
// Create value objects that will be bound to parser variables
Value fVal = 1.11;
Value sVal = "hello world";
Value arr1(3, 0);
arr1[0] = 1.11,
arr1[1] = 2.22;
arr1[2] = 3.33;
Parser parser;
// Define parser variables and bind them to their value objects
parser.DefineVar("va", Variable(&arr1));
parser.DefineVar("a", Variable(&fVal));
parser.DefineVar("sa", Variable(&sVal));
parser.SetExpr("sin(a)+b");
// The returned result is of type Value, value is a Variant like
// type that can be either a boolean an integer or a floating point value
Value result = parser.Eval();
// Value supports C++ streaming like this:
cout << "Result:\n" << result << "\n";
// Or if you need the specific type use this:
switch (result.GetType())
{
case 's': cout << result.GetString() << " (string)" << "\n"; break;
case 'i': cout << result.GetInt() << " (int)" << "\n"; break;
case 'f': cout << result.GetFloat() << " (float)" << "\n"; break;
case 'c': cout << result.GetFloat() << "+" << result.GetImag() << "i (complex)" << "\n"; break;
case 'b': break;
}
}
catch(ParserError &e)
{
cout << e.GetMsg() << "\n\n";
if (e.GetContext().Ident.length())
cout << "Ident.: " << e.GetContext().Ident << "\n";
if (e.GetExpr().length())
cout << "Expr.: " << e.GetExpr() << "\n";
if (e.GetToken().length())
cout << "Token: " << e.GetToken() << "\n";
cout << "Pos: " << e.GetPos() << "\n";
cout << "Errc: " << e.GetCode() << "\n";
}
} // Calc()
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