@safe unittest{    import std.internal.cstring;     version (Posix)    {        import core.stdc.stdlib : free;        import core.sys.posix.stdlib : setenv;        import std.exception : enforce;         void setEnvironment(scope const(char)[] name, scope const(char)[] value)        { enforce(setenv(name.tempCString(), value.tempCString(), 1) != -1); }    }     version (Windows)    {        import core.sys.windows.winbase : SetEnvironmentVariableW;        import std.exception : enforce;         void setEnvironment(scope const(char)[] name, scope const(char)[] value)        { enforce(SetEnvironmentVariableW(name.tempCStringW(), value.tempCStringW())); }    }} nothrow @nogc @system unittest{    import std.internal.cstring;     import core.stdc.string;     string str = "abc";     // Intended usage    assert(strlen(str.tempCString()) == 3);     // Correct usage    auto tmp = str.tempCString();    assert(strlen(tmp) == 3); // or `tmp.ptr`, or `tmp.buffPtr`     // $(RED WARNING): $(RED Incorrect usage)    auto pInvalid1 = str.tempCString().ptr;    const char* pInvalid2 = str.tempCString();    // Both pointers refer to invalid memory here as    // returned values aren't assigned to a variable and    // both primary expressions are ended.}