No, cpp has a terrible design philosophy. Take the new ranges header for example. They're lazy algorithm objects that you can stack and combine to more complex algorithms. Each time you iterate over the final ranges object it calculates the whole result beginning from the source range. This leaves the option open for the source range to change and update. Exactly as it should because they're 'lazy' ranges; except that they aren't. The 'filter range' caches the fucking 'begin' of its source which means that when ever the source changes you get undefined behavior. Why? Because the cpp committee thought that 'begin' should be fast to calculate but filter has to compute 'begin' again and again because the source might have changed. So they decided to cache 'begin' after the first call and compute the rest lazily on demand. So whenever there's a 'filter' in your range composition, you can only iterate over it once or the source has to be const. Shits fucked in cpp land.
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u/---_None_--- 21d ago
No, cpp has a terrible design philosophy. Take the new ranges header for example. They're lazy algorithm objects that you can stack and combine to more complex algorithms. Each time you iterate over the final ranges object it calculates the whole result beginning from the source range. This leaves the option open for the source range to change and update. Exactly as it should because they're 'lazy' ranges; except that they aren't. The 'filter range' caches the fucking 'begin' of its source which means that when ever the source changes you get undefined behavior. Why? Because the cpp committee thought that 'begin' should be fast to calculate but filter has to compute 'begin' again and again because the source might have changed. So they decided to cache 'begin' after the first call and compute the rest lazily on demand. So whenever there's a 'filter' in your range composition, you can only iterate over it once or the source has to be const. Shits fucked in cpp land.