On Thu, Jan 21, 2016 at 05:09:48AM +0000, Basile B. via Digitalmars-d-announce 
> 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.)


Only boring people get bored. -- JM

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