On Thursday, 20 June 2019 at 20:38:48 UTC, Dennis wrote:
On Thursday, 20 June 2019 at 19:09:11 UTC, Emmanuelle wrote:
Is there any trait or Phobos function for transforming a function/delegate/lambda/whatever's body into a string suitable for `mixin(...)`? For example:


If not, is there any way to do this _without_ using strings?

Depends on what you are trying to achieve with mixing in function body code. If you just want to execute the function code, you can just call it (obviously), so I assume you want dynamic scoping (that global variables are overridden by local variables from the caller) or something?

Yeah, I want to be able to basically use mixin templates but with expressions instead, with the code being executed on the scope of the caller, not the callee; but it seems that's impossible without passing strings. For example, I recently hit an issue with closure scoping (https://forum.dlang.org/post/rnxebjcfpmyzptpwz...@forum.dlang.org) that can be worked around by using IIFEs; I thought, hey, maybe I could make a mixin that turns, say, this (taking the example from the post I just linked):

((x) => (int i) { nums[x] ~= i; })(x);

into this:

mixin(capture!(x, (int i) { nums[x] ~= i; });

where the variables I need captured go first there (in this case, only `x`). Of course, that doesn't work unless I use strings everywhere:

mixin(capture!("x", q{(int i) { nums[x] ~= i; }});

which I find rather ugly and inconvenient.

The technique you linked seems interesting but also loads of work so I'll just give up on this idea for now lol. Thanks though!

Reply via email to