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Source for ticket #227
cc
changetime
2012-10-07 12:13:28
component
WG1 - Core
description
On 2 Jul 2011 on <scheme-reports>, Per Bothner [http://lists.scheme-reports.org/pipermail/scheme-reports/2011-July/001142.html wrote]:
What is the thinking as to how quasiquote interacts with
self-referential data structures? Does anyone have an
algorithm to translate these?
Is this valid? Should it be?
{{{
`#0=(,x #0#)
}}}
One could translate this into:
{{{
(let ((tmp (cons x #f)))
(set-cdr! tmp tmp)
tmp)
}}}
Still, a general algorithm doesn't look exactly trivial,
and I haven't seen a published algorithm that does this.
Bonus points for an algorithm that tries to re-use the
reader objects when possible (i.e. that avoids needless
copying).
id
227
keywords
milestone
owner
cowan
priority
minor
reporter
aag
resolution
fixed
severity
status
closed
summary
quasiquote and cycles
time
2011-07-06 01:14:18
type
task
Changes
Change at time 2012-10-07 12:13:28
author
cowan
field
comment
newvalue
oldvalue
3
raw-time
1349586808009045
ticket
227
time
2012-10-07 12:13:28
Change at time 2012-10-07 12:13:28
author
cowan
field
resolution
newvalue
fixed
oldvalue
raw-time
1349586808009045
ticket
227
time
2012-10-07 12:13:28
Change at time 2012-10-07 12:13:28
author
cowan
field
status
newvalue
closed
oldvalue
writing
raw-time
1349586808009045
ticket
227
time
2012-10-07 12:13:28
Change at time 2011-09-12 05:07:03
author
cowan
field
comment
newvalue
oldvalue
2
raw-time
1315778823000000
ticket
227
time
2011-09-12 05:07:03
Change at time 2011-09-12 05:07:03
author
cowan
field
owner
newvalue
cowan
oldvalue
alexshinn
raw-time
1315778823000000
ticket
227
time
2011-09-12 05:07:03
Change at time 2011-09-12 05:07:03
author
cowan
field
status
newvalue
writing
oldvalue
decided
raw-time
1315778823000000
ticket
227
time
2011-09-12 05:07:03
Change at time 2011-09-11 08:06:11
author
cowan
field
comment
newvalue
WG1 voted to add a note explaining that reader label cycles are not allowed within `quasiquote`.
oldvalue
1
raw-time
1315703171000000
ticket
227
time
2011-09-11 08:06:11
Change at time 2011-09-11 08:06:11
author
cowan
field
resolution
newvalue
oldvalue
raw-time
1315703171000000
ticket
227
time
2011-09-11 08:06:11
Change at time 2011-09-11 08:06:11
author
cowan
field
status
newvalue
decided
oldvalue
new
raw-time
1315703171000000
ticket
227
time
2011-09-11 08:06:11