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discard """
output: '''@[1, 2, 3]
@[4.0, 5.0, 6.0]
@[1, 2, 3]
@[4.0, 5.0, 6.0]
@[1, 2, 3]
@[4, 5, 6]'''
"""
# bug #3476
proc foo[T]: var seq[T] =
## Problem! Bug with generics makes every call to this proc generate
## a new seq[T] instead of retrieving the `items {.global.}` variable.
var items {.global.}: seq[T]
return items
proc foo2[T]: ptr seq[T] =
## Workaround! By returning by `ptr` instead of `var` we can get access to
## the `items` variable, but that means we have to explicitly deref at callsite.
var items {.global.}: seq[T]
return addr items
proc bar[T]: var seq[int] =
## Proof. This proc correctly retrieves the `items` variable. Notice the only thing
## that's changed from `foo` is that it returns `seq[int]` instead of `seq[T]`.
var items {.global.}: seq[int]
return items
foo[int]() = @[1, 2, 3]
foo[float]() = @[4.0, 5.0, 6.0]
foo2[int]()[] = @[1, 2, 3]
foo2[float]()[] = @[4.0, 5.0, 6.0]
bar[int]() = @[1, 2, 3]
bar[float]() = @[4, 5, 6]
echo foo[int]() # prints 'nil' - BUG!
echo foo[float]() # prints 'nil' - BUG!
echo foo2[int]()[] # prints '@[1, 2, 3]'
echo foo2[float]()[] # prints '@[4.0, 5.0, 6.0]'
echo bar[int]() # prints '@[1, 2, 3]'
echo bar[float]() # prints '@[4, 5, 6]'
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