d102b2f54c* deprecate unsafeAddr; extend addr addr is now available for all addressable locations, unsafeAddr is deprecated and become an alias for addr * follow @Vindaar's advice * change the signature of addr * unsafeAddr => addr (stdlib) * Update changelog.md * unsafeAddr => addr (tests) * Revert "unsafeAddr => addr (stdlib)" This reverts commit ab83c99c507048a8396e636bf22d55fdd84d7d1c. * doc changes; thanks to @konsumlamm Co-authored-by: konsumlamm <44230978+konsumlamm@users.noreply.github.com> Co-authored-by: konsumlamm <44230978+konsumlamm@users.noreply.github.com>
47 lines
1.3 KiB
Nim
47 lines
1.3 KiB
Nim
discard """
|
|
errormsg: "cannot cast to a non concrete type: 'ptr SomeNumber'"
|
|
line: 36
|
|
"""
|
|
|
|
# https://github.com/nim-lang/Nim/issues/5428
|
|
|
|
type
|
|
MemFile = object
|
|
mem: pointer
|
|
|
|
proc memfileopen(filename: string, newFileSize: int): MemFile =
|
|
# just a memfile mock
|
|
return
|
|
|
|
type
|
|
MyData = object
|
|
member1: seq[int]
|
|
member2: int
|
|
|
|
type
|
|
MyReadWrite = object
|
|
memfile: MemFile
|
|
offset: int
|
|
|
|
# Here, SomeNumber is bound to a concrete type, and that's OK
|
|
proc write(rw: var MyReadWrite; value: SomeNumber): void =
|
|
(cast[ptr SomeNumber](cast[uint](rw.memfile.mem) + rw.offset.uint))[] = value
|
|
rw.offset += sizeof(SomeNumber)
|
|
|
|
# Here, we try to use SomeNumber without binding it to a type. This should
|
|
# produce an error message for now. It's also possible to relax the rules
|
|
# and allow for type-class based type inference in such situations.
|
|
proc write[T](rw: var MyReadWrite; value: seq[T]): void =
|
|
rw.write value.len
|
|
let dst = cast[ptr SomeNumber](cast[uint](rw.memfile.mem) + uint(rw.offset))
|
|
let src = cast[pointer](value[0].addr)
|
|
let size = sizeof(T) * value.len
|
|
copyMem(dst, src, size)
|
|
rw.offset += size
|
|
|
|
proc saveBinFile(arg: var MyData, filename: string): void =
|
|
var rw: MyReadWrite
|
|
rw.memfile = memfileOpen(filename, newFileSize = rw.offset)
|
|
rw.offset = 0
|
|
rw.write arg.member1
|
|
|