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Hi,

From logical point of view NAN || logic expression returns a logic expression, but logic expression || NAN returns NAN. In general, I'm missing a lot of if isnan() conditions in the code to catch NAN values, for example also for OP_LOGICAL_AND, NAN would also occur here if and only if the second expression is NAN.

Kind regards,

Thaddäus

Hi.

Firstly, thanks for this great job!

So, I noticed the library doesn't contains any error handling, and this would be very useful to find errors in complex expressions.

Edit: it was implemented in 2034c85.

cheers

Looks like the return type of expr_eval() is float which is 32 bit wide on my 64 bit system. Is it possible to use double which is of 64 bits while evaluating an expression?

The example doesn't compile but a little correction does:

#include "expr.h"

// Custom function that returns the sum of its two arguments
static float add(struct expr_func *f, vec_expr_t args, void *c) {
  float a = expr_eval(&vec_nth(&args, 0));
  float b = expr_eval(&vec_nth(&args, 1));
  return a + b;
}

static struct expr_func user_funcs[] = {
	{"add", add, 0},
	{NULL, NULL, 0},
};

int main() {
	char* a = (char*)malloc(40);
	const char *s = "x = 5, add(2, x)";
  struct expr_var_list vars = {0};
  struct expr *e = expr_create(s, strlen(s), &vars, user_funcs);
  if (e == NULL) {
    printf("Syntax error");
		return 1;
	}

	float result = expr_eval(e);
	printf("result: %f\n", result);

	expr_destroy(e, &vars);
	return 0;
}

However, it doesn't work as expected.

There seems to be issues with anonymous unions and also with casting function pointers to void*

here are the flags I use

CFLAGS:= -Wfatal-errors -pedantic -Wall -Wextra -Werror -std=c99

While this might seem over fussy, its saved me countless hours of debugging frustration!

This is not an issue, rather a question.

Why is this library implemented as a .h file and not in a .c file? Are there any reason for this excluding performance?