template `=~`*(s: string, pattern: TPeg): bool =
when not definedInScope(matches):
var matches: array[0..maxSubpatterns-1, string]
It seems that this never worked as intended.
I discovered it now, because when variables' names are preserved, multiple
variables named `matches` were created. The reason this happens is that
when the template is used as an if condition, the if scope is already entered,
but the variables end up in the outer scope.
This patch is consistent with how `expr` templates work, but makes the
definition of a variable injection template like := a bit harder, yet still possible.
(note that if foo := bar(): is still not creating properly scoped variable prior to the patch)
even thought the setjmp implementation for try statement won't be used in C++,
using properly scoped variables for them is beneficial, because we'll be able to
establish a 1:1 relation between nimrod scopes and C scopes.
Once we have that, we'll be able to keep the original names of local variables
to greatly improve the debugging experience (i.e. watch expressions and
hover tooltips will work).
types are now valid proc/template/macro params and you can overload over them:
proc foo(T: typedesc) # accept any type
proc foo(T: typedesc{int}) # overload specifically for int
proc foo(T: typedesc{int or float or Callable}) # overload for any type matching the constraints
expr{type} is a param expecting compile time value of the designated type (or type class).
when typedesc or expr params are used with a proc, the proc will be instantiated once
for each unique type/value used as parameter.
