beef331 / constructor Goto Github PK

when trying the example code:

import constructor/defaults
type Thingy{.defaults.} = object
  a: float = 10 # Can do it this way
  b = "Hmm" # Can also do it this way
  c = 10
implDefaults(Thingy) # Required to embed the procedure
assert initThingy() == Thingy(a: 10, b: "Hmm", c: 10)

with the flag --experimental:strictFuncs set, the compiler complains:
..../.nimble/pkgs/micros-0.1.5/micros/definitions/routines.nim(109, 49) template/generic instantiation of & from here
..../nim-1.6.6/lib/system.nim(1675, 8) Error: '&' can have side effects an object reachable from 'x' is potentially mutated
..../nim-1.6.6/lib/system.nim(1689, 23) the mutation is here
..../nim-1.6.6/lib/system.nim(1689, 23) is the statement that connected the mutation to the parameter

It would be nice to be able to use the lib independently of that flag.

Taken from a larger project, source is here: https://github.com/ajusa/dalo/blob/master/src/dalo.nim

Here's the code:

proc initField*(label = "", default = "", widget = defaultInput): Field
  Field(label: label, widget: widget, default: default)

The constructor version of this causes a segfault, whereas having the proc above doesn't call a segfault. widget is of type

  Widget* = proc(f: Field, value: string, error: string): VNode {.closure.}

Since it seems to segfault when I call render (which calls the Widget proc) I can only assume that something related to that is causing the segfault. Hopefully that's enough for you, let me know if you need more information!

type FileInfo* = object
  path*: string
  size*: BiggestInt
  exists*: bool

type Image* = object
  file*: FileInfo
  dest*: string
  date*: DateTime

Doing

proc initImage*(file: FileInfo, dest: string, lastModified: Time): Image =
Image.init(file, dest, lastModified.inZone(local()))

results in the error Error: unhandled exception: index out of bounds, the container is empty [IndexDefect] I can only assume this has to do with the nested object, as your tests seem to pass.

Attempting to use defaults with generic objects results in compiler errors both with {} and {defTypeConstr}. We likely need to lift the generic parameters and add them to the procedures. Then use Inner[T] everywhere instead of Inner.

@Patitotective no clue if you have any interest in throwing darts and seeing what lands. Totally up to you.

Heyho, I am using constructor together with orm for convenience purposes and stumbled over this bug:

import norm/[model, pragmas]
import constructor/defaults
import std/times

type 
Item* {.defaults, tableName: "atable".} = ref object of Model
  name*: string = ""
  campaign_id*: int64 = -2
  update_datetime*: DateTime = now()
  creation_datetime*: DateTime = now()
  
implDefaults(Item)

let i1 = newItem() # Works but should it?
#let i2 = initItem() # does not compile

According to what we discussed on discord, the object as a value-allocated type Item should create a initItem() in accordance with nim best practices.
Instead it gets a newItem() proc like a heap allocated object.

This appears to be an issue due to inheritance in the type.

We had discussed this one on discord a couple days back. Having runable examples for the macros and doc comments could be useful.

I'll make a PR to add some that you can do with as you please, just wanted to contribute something mildly useful.

To do this we should replace the bool exported with a bitset that allows features as we go, such as defTypeInit.