template/macro pragmas don't work in templates (eg: byaddr, since etc)

[Clonkk]

Using byaddrin a template does not compile while the same code inside a block works.

Example

import std/decls

template test(x: string)=
  var y {.byaddr.} = x
  echo y
 
var xx = "123"
test(xx)

Current Output

 template/generic instantiation of `test` from here
 Error: invalid pragma: byaddr

Expected Output

123

$ nim -v

Nim Compiler Version 1.5.1 [Linux: amd64]
Compiled at 2020-11-11
Copyright (c) 2006-2020 by Andreas Rumpf

git hash: bbe49a14ae827b6474d692042406716a3b3dd71f
active boot switches: -d:release

[EDIT]

• see also: Using byaddr pragma inside template - Nim forum

[ringabout]

There are some problems with using user-defined pragmas in templates

template pro(a: untyped) =
  discard

template test() =
  var y {.pro.} = 10

test()

They are both related to resolveOverloads.

[timotheecour]

I've been tracking this + related issues, this isn't specific to byaddr but is more general:

• invalid pragma for var pragmas inside templates timotheecour/Nim#89
  invalid pragma for var pragmas inside templates

template foo(lhs, typ, expr) =
  let lhs = expr
proc fun1()=
  let a {.foo.} = 1
template fun2()=
  let a {.foo.} = 1
fun1() # ok
fun2() # BUG: Error: invalid pragma: foo

• cannot attach a custom pragma to templates timotheecour/Nim#129
  cannot attach a custom pragma to templates

template bar(a, body: untyped) {.dirty, used.} = discard
proc fun1() {.bar: 1.} = discard # ok
template fun2() {.bar: 1.} = discard # error: Error: cannot attach a custom pragma to 'fun2'

when false: # ditto with these
  template bar2(body: untyped) {.dirty, used.} = discard
  template bar3(body: untyped) = discard
  template fun2() {.bar2.} = discard
  template fun3() {.bar3.} = discard

• since doesn't work with templates since doesn't work with templates timotheecour/Nim#42
  see [WIP] exportable pragmas #13016 (comment)

• {.pragma: callfun, fun.} doesn't work with :
  {.pragma: noNimScript, macropragma.} does not work timotheecour/Nim#142

template fun(body: untyped): untyped = echo "ok1"
{.pragma: callfun, fun.}
proc bar1() {.fun.} = echo "ok2" # ok
proc bar2() {.callfun.} = echo "ok2" # Error: invalid pragma: fun

related WIP PR's

• fix: var a{.foo.} = expr inside templates (refs #15920) (except when foo is overloaded) #13869
• [WIP] exportable pragmas #13016