issues using generic parameters in template

[jcosborn]

In template fooT[T](x: A[T]) calling foo(T), which is a proc, crashes the compiler and calling fooT(T), which is a template, matches the int overload instead of typedesc[int].

type
  A[T] = object
    v: T

proc foo(x: int) = echo "int"
proc foo(x: typedesc[int]) = echo "typedesc[int]"
template fooT(x: int) = echo "int"
template fooT(x: typedesc[int]) = echo "typedesc[int]"

proc foo[T](x: A[T]) =
  foo(T)   # typedesc[int]  (correct)
  fooT(T)  # typedesc[int]  (correct)

template fooT[T](x: A[T]) =
  foo(T)   # typedescparam.nim(20, 5) Error: internal error: expr(skType); unknown symbol
  fooT(T)  # int  (should be typedesc[int])

var x: A[int]
foo(x)
fooT(x)

[jxy]

Right. I have been using workarounds like this:

type
  A[T] = object
    v: T

proc foo(x: int) = echo "int"
proc foo(x: typedesc[int]) = echo "typedesc[int]"
template fooT(x: int) = echo "int"
template fooT(x: typedesc[int]) = echo "typedesc[int]"

proc foo(x: A) =
  foo(x.T)
  fooT(x.T)

template fooT(x: A) =
  foo(x.T)
  fooT(x.T)

var x: A[int]
foo(x)
fooT(x)

[genotrance]

Still crashes with #head, full stacktrace below.

-------- SNIPPET --------
type
  A[T] = object
    v: T

proc foo(x: int) = echo "int"
proc foo(x: typedesc[int]) = echo "typedesc[int]"
template fooT(x: int) = echo "int"
template fooT(x: typedesc[int]) = echo "typedesc[int]"

proc foo[T](x: A[T]) =
  foo(T)   # typedesc[int]  (correct)
  fooT(T)  # typedesc[int]  (correct)

template fooT[T](x: A[T]) =
  foo(T)   # typedescparam.nim(20, 5) Error: internal error: expr(skType); unknown symbol
  fooT(T)  # int  (should be typedesc[int])

var x: A[int]
foo(x)
fooT(x)
-------------------------

-------- OUTPUT --------
Hint: used config file 'c:\users\gt\Desktop\DL\programming\nimdevel\config\nim.cfg' [Conf]
Hint: system [Processing]
Hint: temp [Processing]
temp.nim(20, 5) Error: internal error: expr(skType); unknown symbol
No stack traceback available
To create a stacktrace, rerun compilation with ./koch temp c <file>
------------------------

-------- NIMTEMP --------
Hint: used config file 'c:\users\gt\Desktop\DL\programming\nimdevel\config\nim.cfg' [Conf]
Hint: system [Processing]
Hint: temp [Processing]
temp.nim(20, 5) Error: internal error: expr(skType); unknown symbol
Traceback (most recent call last)
nim.nim(133)             nim
nim.nim(97)              handleCmdLine
main.nim(162)            mainCommand
main.nim(73)             commandCompileToC
modules.nim(124)         compileProject
modules.nim(71)          compileModule
passes.nim(194)          processModule
passes.nim(103)          processTopLevelStmt
cgen.nim(1379)           myProcess
ccgstmts.nim(1150)       genStmts
ccgexprs.nim(2257)       expr
ccgexprs.nim(2041)       genStmtList
ccgstmts.nim(1150)       genStmts
ccgexprs.nim(2223)       expr
ccgcalls.nim(548)        genCall
ccgcalls.nim(187)        genPrefixCall
ccgcalls.nim(170)        genArg
cgen.nim(496)            initLocExprSingleUse
ccgexprs.nim(2204)       expr
msgs.nim(524)            internalError
msgs.nim(495)            liMessage
msgs.nim(324)            handleError
msgs.nim(314)            quit
-------------------------

-------- VERSION --------
Nim Compiler Version 0.18.1 [Windows: i386]
Compiled at 2018-07-02
Copyright (c) 2006-2018 by Andreas Rumpf

git hash: d1f983b37cf1b0aa03b1424c3cca9d4212558db9
active boot switches: -d:release
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