nth::scope

Simplest possible header-only C++17 scope-guard library for cleanup at scope exit, which provides two tiny types:

• nth::scope_exit_t — non-dismissable guard that always runs on scope exit
• nth::scope_fuse_t — dismissable guard that can be invoked or released early

Both are designed to have minimal size overhead even in debug builds to be embedded friendly.

Usage

Just copy include/nth/scope.h into your project directly or add the library with CMake (recommended):

add_subdirectory(scope)
target_link_libraries(your_target PRIVATE scope)
target_compile_features(your_target PRIVATE cxx_std_17)

And include the header:

#include <nth/scope.h>

Example

{
    int i = 42;

    nth::scope_exit_t on_exit_1 = [&] {
        printf("on_exit_1: %d\n", i);
    };
    nth::scope_exit_t on_exit_2 = [] {
        printf("on_exit_2\n");
    };
    nth::scope_fuse_t on_exit_3 = [] {
        printf("on_exit_3\n");
    };
    nth::scope_fuse_t on_exit_4 = [] {
        printf("on_exit_4\n");
    };

    on_exit_3.invoke(); // invoke before scope exit
    // on_exit_3
    on_exit_3.invoke(); // no-op
    on_exit_3.defuse(); // no-op

    on_exit_4.defuse(); // cancel before scope exit

    // ~on_exit_4 won't be invoked
    // ~on_exit_3 won't be invoked

    // on_exit_2
    // on_exit_1: 42
}