hasufell
/
ghcup-hs
1
1
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Update hacking doc

This commit is contained in:
Julian Ospald 2020-04-13 15:20:56 +02:00
parent aedfc19220
commit 78d36bce24
No known key found for this signature in database
GPG Key ID: 511B62C09D50CD28
1 changed files with 17 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
HACKING.md
View File

@ -16,7 +16,23 @@ I consider haskell-TLS an interesting experiment, but not a battle-tested and pe
### Optics instead of lens
They're a little safer (less Monoid weirdness with view) and have better error messages. Consider: `view (_Just . to (++ "abc")) Nothing` (lens) vs `view (_Just % to (++ "abc")) Nothing` (optics). The latter does not compile (good).
They're a little safer (less Monoid weirdness with view) and have better error messages. Consider the following wit lens
```
> view (_Just . to (++ "abc")) Nothing
""
```
vs optics
```
view (_Just % to (++ "abc")) Nothing
<interactive>:2:1: error:
• An_AffineFold cannot be used as A_Getter
• In the expression: view (_Just % to (++ "abc")) Nothing
In an equation for ‘it’: it = view (_Just % to (++ "abc")) Nothing
```
### Strict and StrictData on by default