[bjourne]

"Optimized" string types are everywhere and I bet that multiple people have already created string types almost identical to German strings. But the memory savings are small and they are not more efficient than ordinary strings. For string comparison you compare the pointers, which is cheaper than comparing two pairs of registers. If the pointers mismatch you compare the (cached) hashes and only if they match do you need to compare characters. For the prefix query, starts_with(content, 'http'), just store a string of the four-character prefix. With immutable strings the overhead is just one pointer.

[f1shy]

Do you have a pointer to real world data about the effectiveness of these optimizations? I learned about it (SSO, in std lib which is basically the same) in an article which really made it look as that would make anything in C++ blazing fast. In the codebases I worked, a couple of times, I did measure (what you shoud do before optimizing) and the results where between absolutely negligible to worst when active. But that were 3 data points. Mind you one in a real time database.