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#include "tinyexpr.h"
#include <stdio.h>
int main(int argc, char *argv[])
{
if (argc < 2) {
printf("Usage: example2 \"expression\"\n");
return 0;
}
const char *expression = argv[1];
printf("Evaluating:\n\t%s\n", expression);
/* This shows an example where the variables
* x and y are bound at eval-time. */
double x, y;
te_variable vars[] = {{"x", &x}, {"y", &y}};
/* This will compile the expression and check for errors. */
int err;
te_expr *n = te_compile(expression, vars, 2, &err);
if (n) {
/* The variables can be changed here, and eval can be called as many
* times as you like. This is fairly efficient because the parsing has
* already been done. */
x = 3; y = 4;
const double r = te_eval(n); printf("Result:\n\t%f\n", r);
te_free(n);
} else {
/* Show the user where the error is at. */
printf("\t%*s^\nError near here", err-1, "");
}
return 0;
}
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