c_NPOS is not -1, differs from `std::string::npos` #103

liigo · 2024-10-15T10:37:39Z

in C++, the std::string::npos is -1, so someone may write:

string s = "test";
int i = s.find('e');
if (i >= 0) // same as `i != std::string::npos`
    cout << "found it at " << i << "\n";

but STC's c_NPOS is defined as INTPTR_MAX which is not -1.
if you check i >= 0, then the code is error-prone.

The text was updated successfully, but these errors were encountered:

tylov · 2024-10-15T21:31:29Z

I will consider changing to -1 because of some other reason, but it is more complicated:
In c++, npos is of type size_t which is unsigned the largest number possible, but switching type or relying on the value of npos is not good. There are some functions, e.g. cstr_subview(s, pos, len), where you can pass in c_POS for len, and it will return to the end of the view (it stops at which comes first). I think this is also how it is working for some functions in c++.

liigo · 2025-01-13T14:05:21Z

outdated (v5 was out) , closing

liigo closed this as completed Jan 13, 2025

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c_NPOS is not -1, differs from `std::string::npos` #103

c_NPOS is not -1, differs from `std::string::npos` #103

c_NPOS is not -1, differs from std::string::npos #103

c_NPOS is not -1, differs from std::string::npos #103

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c_NPOS is not -1, differs from `std::string::npos` #103

c_NPOS is not -1, differs from `std::string::npos` #103