Make tryEval work on fetchurl

[copumpkin]

They apparently don't work together right now which is why @aszlig went for this abomination: https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/networking/browsers/chromium/update.nix#L163-L166

cc @edolstra @shlevy for a laugh if nothing else 😄

[edolstra]

Errors in builtins.fetchurl are not supposed to be catchable to ensure reproducibility of evaluations.

[copumpkin]

Fair enough, so I guess we stick with the md5 collision :D

…

On Feb 2, 2017, at 15:20, Eelco Dolstra ***@***.***> wrote: Errors in builtins.fetchurl are not supposed to be catchable to ensure reproducibility of evaluations. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[edolstra]

I don't understand what all that code is for. It looks like it's using Nix for something it's not intended for.

[copumpkin]

I think any time you intentionally use an md5 collision in your application logic, something is probably a bit iffy :) Basically it's all trying to use Nix to determine if a new version is available, which by definition is not deterministic. Maybe I should link to #520 again!

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On Thu, Feb 2, 2017 at 16:13 Eelco Dolstra ***@***.***> wrote: I don't understand what all that code is for. It looks like it's using Nix for something it's not intended for. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#1214 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAKP2iWRjwb1LI91qecnbBFkxJiNdLUks5rYfKqgaJpZM4L1Fka> .

[stale]

I marked this as stale due to inactivity. → More info