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Source for ticket #33
cc
changetime
2011-01-24 08:12:22
component
WG1 - Core
description
New to R5RS, do we reaffirm the sometimes debated dynamic-wind?
id
33
keywords
milestone
owner
alexshinn
priority
major
reporter
alexshinn
resolution
wontfix
severity
status
closed
summary
dynamic-wind
time
2010-02-23 17:07:10
type
defect
Changes
Change at time 2011-01-24 08:12:22
author
cowan
field
comment
newvalue
oldvalue
8
raw-time
1295827942000000
ticket
33
time
2011-01-24 08:12:22
Change at time 2011-01-24 08:12:22
author
cowan
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resolution
newvalue
wontfix
oldvalue
raw-time
1295827942000000
ticket
33
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2011-01-24 08:12:22
Change at time 2011-01-24 08:12:22
author
cowan
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status
newvalue
closed
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reopened
raw-time
1295827942000000
ticket
33
time
2011-01-24 08:12:22
Change at time 2011-01-24 08:12:05
author
cowan
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comment
newvalue
oldvalue
7
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1295827925000000
ticket
33
time
2011-01-24 08:12:05
Change at time 2011-01-24 08:12:05
author
cowan
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resolution
newvalue
oldvalue
fixed
raw-time
1295827925000000
ticket
33
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2011-01-24 08:12:05
Change at time 2011-01-24 08:12:05
author
cowan
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status
newvalue
reopened
oldvalue
closed
raw-time
1295827925000000
ticket
33
time
2011-01-24 08:12:05
Change at time 2010-10-18 02:32:39
author
cowan
field
comment
newvalue
The WG voted to reaffirm R5RS `dynamic-wind` as part of the core.
oldvalue
6
raw-time
1287343959000000
ticket
33
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2010-10-18 02:32:39
Change at time 2010-10-18 02:32:39
author
cowan
field
resolution
newvalue
fixed
oldvalue
raw-time
1287343959000000
ticket
33
time
2010-10-18 02:32:39
Change at time 2010-10-18 02:32:39
author
cowan
field
status
newvalue
closed
oldvalue
new
raw-time
1287343959000000
ticket
33
time
2010-10-18 02:32:39
Change at time 2010-03-17 03:27:11
author
kumoyuki
field
comment
newvalue
Replying to [comment:4 cowan]:
> First of all, nothing is beyond the scope of WG1 unless WG1 declares it so, which has not happened.
Well it's clear we all have opinions on where the boundaries should lie. Or was that WG2 we signed up for?
> Second, not standardizing threads is not equivalent to standardizing the absence of threads.
This is precisely my point. Thank you.
> All major Scheme implementations have threads, and that can't just be ignored.
As far as I can tell Larceny as of v0.97 doesn't, although the source code contains strong hints that they have been working on the ideas. Or maybe Larceny isn't a major implementation in your sight.
> Finally, the fact that a procedure can be implemented in terms of existing procedures has never been a bar to standardizing it.
If you have only winding continuations you have no other options. If you have classic call-with-current-continuation, you can have both. Additionally, the case of dynamic-wind however, is a fairly clear case of moving in exactly the opposite direction of the Prime Clingerism. WG2 is far less constrained in those terms.
oldvalue
4.5
raw-time
1268771231000000
ticket
33
time
2010-03-17 03:27:11
Change at time 2010-03-16 20:24:42
author
cowan
field
comment
newvalue
First of all, nothing is beyond the scope of WG1 unless WG1 declares it so, which has not happened.
Second, not standardizing threads is not equivalent to standardizing the absence of threads. All major Scheme implementations have threads, and that can't just be ignored.
Finally, the fact that a procedure can be implemented in terms of existing procedures has never been a bar to standardizing it. As obvious examples, consider ABS, GCD, LCM, INTEGER?, ZERO? and friends, MAX, MIN, NUMBER->STRING, STRING->NUMBER, LIST, LENGTH, APPEND, REVERSE, LIST-TAIL, ASSOC and friends, MEMBER and friends, CHAR=? and friends, STRING, STRING-APPEND, STRING->LIST, LIST->STRING, VECTOR, MAP, FOR-EACH, EVAL, WITH-*-*-FILE, WRITE, DISPLAY, NEWLINE/.
oldvalue
4
raw-time
1268745882000000
ticket
33
time
2010-03-16 20:24:42
Change at time 2010-03-16 13:40:22
author
kumoyuki
field
comment
newvalue
Threading requires primitives beyond the scope of WG1. QED.
oldvalue
3
raw-time
1268721622000000
ticket
33
time
2010-03-16 13:40:22
Change at time 2010-03-16 11:36:02
author
cowan
field
comment
newvalue
Not in Schemes which provide threads.
oldvalue
2
raw-time
1268714162000000
ticket
33
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2010-03-16 11:36:02
Change at time 2010-03-16 05:20:00
author
kumoyuki
field
comment
newvalue
No. dynamic-wind is properly the realm of WG2 as it is directly implementable on top of the R4RS non-winding call-with-current-continuation.
oldvalue
1
raw-time
1268691600000000
ticket
33
time
2010-03-16 05:20:00
Change at time 2010-03-16 05:20:00
author
kumoyuki
field
milestone
newvalue
oldvalue
raw-time
1268691600000000
ticket
33
time
2010-03-16 05:20:00