niedz., 5 lis 2023 o 23:55 Bjorn Reese via Std-Proposals
<std-proposals_at_[hidden]> napisał(a):
>
> On 11/5/23 21:38, Frederick Virchanza Gotham via Std-Proposals wrote:
> > Today I was programming an Arduino microcontroller and I wrote the
> > following loop:
> >
> > for ( ; Serial.available(); ++p )
> > {
> > if ( p >= &buf[sizeof(buf) - 1u] ) break;
> > p[0u] = Serial.read();
> > p[1u] = '\0';
> > unsigned const len = std::strlen(buf);
> > char *ending = nullptr;
> > if ( nullptr != (ending = std::strstr(buf, "\r\n")) )
> > {
> > ending[0u] = '\0';
> > ending[1u] = '\0'; // Overwrite the "\r\n" with "\0\0"
> > if ( ending != buf ) this->ProcessInput();
> > buf[0u] = '\0';
> > p = buf - 1u; // subtract 1 because it will be
> > incremented upon continuing
> > }
> > }
>
> The usual solution is to move the increment into the loop
>
> while (Serial.available()) {
> // Do stuff
> if (condition) {
> // Do conditional stuff
> p = buf;
> } else {
> ++p;
> }
> }
>

There is idiom like this with `erase`:

```
if (condition)
{
    p = v.erase(p);
}
else
{
    ++p;
}
```

but do not know if this is good code practice as it is very easy to
make mistakes.
A lot better is make helper function that will handle all tricky iterations:

```
process_and_errase_if(v, [&](auto& a) { /*procesing*/ return condition; });
```

And this could be done initial example:

```
process<Serial>(buff, [&](auto val){
    /*procesing*/
    if (condition1) return Process::Continue;
    else if (condition2) return Process::Repeat;
    else return Process::Break;
});
```

all ugly and comlex code will be hidden in `process<Serial>` function.



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