On Thu, Jan 21, 2016 at 05:09:48AM +0000, Basile B. via Digitalmars-d-announce wrote: [...] > I mean '@safe' at too low level is a handicap. It's like 'const'. They > are hard to use, mostly because of transitivness. These attributes are > never a noop.
Transitivity also makes const really painful to use in a widespread way. I've tried writing const-correct code before too, but gave up because it quickly became too unwieldy to work with. I started spending more time hunting down missing const attributes than actually writing useful code, so I decided it was time to give up. Generally, though, const is still useful in lower-level code (i.e., near the leaf nodes of your function call tree), to prevent silly mistakes. Knowing how to use const is also helpful in utility functions that need to accept both immutable and mutable, etc.. Just like with (the current state of) @safe, though, pervasive use of const is still too onerous currently. Transitivity really makes it painful, especially when important chunks of Phobos still isn't fully const-correct (or at least const-compatible) yet. A lot of progress has been made, but, const being transitive, all it takes is for one small Phobos function to be non-const when it should be const, and your entire call tree can no longer be const. Encounter this a handful of times, and it's hard not to just throw in the towel instead of spending all of your time working around const issues rather than writing useful code. (Recently I'm slowly moving towards writing *all* my code as template functions, and letting the compiler do the tedious work of attributing my code instead of typing them out myself. My secret wish is that one day, the compiler's attribute inference will be good enough that I could just slap one or two const's (or @safe, etc.) on top of my modules and everything will Just Work.) T -- Only boring people get bored. -- JM
