Re: [PIC] Learning C

On Sun, 10 Nov 2024, Neil wrote:

> Agree with a couple things from other comments such as C being high-level 
> assembler and using a PC at first (you can just use gcc already on Linux).
>
> Already knowing a structured language is very helpful.
> But IMO you'll have to wrap your head around pointers, which can get 
> confusing. I find this C visualizer very helpful for figuring out some 
> algorithm... https://pythontutor.com/c.html
>
> One more note: = != ==
> Or in other words, the equal sign ( = ) and the double equal size ( == ) are 
> very different things in C. The first assigns a value and the other compares 
> values. But people new to C will invariably use a single equal for a 
> comparison and the code is true every time, as C will compile it as valid 
> code, do the assignment, then the comparison. You have been warned ;P

Sorry to wade in here but:

if (y = x)...

assigns x to y then compares the result to 0. 0 is nomally taken to
mean false and "not 0" as true. So it is almost alway true except in the 
case where x is 0.

I'm not sure what happens if x and y are floats and x is a NaN or if x and 
y are structures.

if you're looking for a real headache try debugging a program that 
contains:

if (! x == y)...

Trying to learn C on bare metal is like trying to learn to fly by crashing 
a lot. It's a lot quicker and easier if you learn on a simulator.

Friendly Regards
Sergio Masci