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Source for ticket #16
cc
changetime
2012-10-04 23:54:01
component
WG1 - Reader Syntax
description
[This ticket was originally about string escapes, but commenters have been talking about symbol escapes instead.]
R6RS provides character escapes in symbols of the form `\xnnnn;`, where nnnn is 1-5 hex digits. Do we accept this extension? Do we also allow |...| to escape a whole symbol or a part of one?
id
16
keywords
milestone
owner
alexshinn
priority
major
reporter
alexshinn
resolution
fixed
severity
status
closed
summary
symbol escapes
time
2010-02-23 16:36:44
type
defect
Changes
Change at time 2012-10-04 23:54:01
author
cowan
field
comment
newvalue
oldvalue
15
raw-time
1349369641280937
ticket
16
time
2012-10-04 23:54:01
Change at time 2012-10-04 23:54:01
author
cowan
field
resolution
newvalue
fixed
oldvalue
raw-time
1349369641280937
ticket
16
time
2012-10-04 23:54:01
Change at time 2012-10-04 23:54:01
author
cowan
field
status
newvalue
closed
oldvalue
writing
raw-time
1349369641280937
ticket
16
time
2012-10-04 23:54:01
Change at time 2011-02-19 20:04:54
author
alexshinn
field
comment
newvalue
oldvalue
14
raw-time
1298117094000000
ticket
16
time
2011-02-19 20:04:54
Change at time 2011-02-19 20:04:54
author
alexshinn
field
owner
newvalue
alexshinn
oldvalue
raw-time
1298117094000000
ticket
16
time
2011-02-19 20:04:54
Change at time 2011-02-19 20:04:54
author
alexshinn
field
status
newvalue
writing
oldvalue
decided
raw-time
1298117094000000
ticket
16
time
2011-02-19 20:04:54
Change at time 2011-01-29 11:43:36
author
alexshinn
field
comment
newvalue
oldvalue
13
raw-time
1296272616000000
ticket
16
time
2011-01-29 11:43:36
Change at time 2011-01-29 11:43:36
author
alexshinn
field
status
newvalue
decided
oldvalue
assigned
raw-time
1296272616000000
ticket
16
time
2011-01-29 11:43:36
Change at time 2011-01-29 11:43:26
author
alexshinn
field
comment
newvalue
oldvalue
12
raw-time
1296272606000000
ticket
16
time
2011-01-29 11:43:26
Change at time 2011-01-29 11:43:26
author
alexshinn
field
owner
newvalue
oldvalue
alexshinn
raw-time
1296272606000000
ticket
16
time
2011-01-29 11:43:26
Change at time 2011-01-29 11:43:26
author
alexshinn
field
status
newvalue
assigned
oldvalue
reopened
raw-time
1296272606000000
ticket
16
time
2011-01-29 11:43:26
Change at time 2011-01-29 11:43:13
author
alexshinn
field
comment
newvalue
oldvalue
11
raw-time
1296272593000000
ticket
16
time
2011-01-29 11:43:13
Change at time 2011-01-29 11:43:13
author
alexshinn
field
resolution
newvalue
oldvalue
fixed
raw-time
1296272593000000
ticket
16
time
2011-01-29 11:43:13
Change at time 2011-01-29 11:43:13
author
alexshinn
field
status
newvalue
reopened
oldvalue
closed
raw-time
1296272593000000
ticket
16
time
2011-01-29 11:43:13
Change at time 2010-10-18 03:06:56
author
cowan
field
comment
newvalue
The WG voted to accept this feature.
oldvalue
10
raw-time
1287346016000000
ticket
16
time
2010-10-18 03:06:56
Change at time 2010-10-18 03:06:56
author
cowan
field
resolution
newvalue
fixed
oldvalue
raw-time
1287346016000000
ticket
16
time
2010-10-18 03:06:56
Change at time 2010-10-18 03:06:56
author
cowan
field
status
newvalue
closed
oldvalue
new
raw-time
1287346016000000
ticket
16
time
2010-10-18 03:06:56
Change at time 2010-03-20 16:06:51
author
kumoyuki
field
comment
newvalue
Replying to [comment:7 cowan]:
It seems that there is an unfortunate consequence of using Trac for the purpose of discussing language design issues. I am fine with the string escapes, but there is a side effect in another area - namely symbols, where the string escapes are less than pleasing.
oldvalue
7.9
raw-time
1269076011000000
ticket
16
time
2010-03-20 16:06:51
Change at time 2010-03-20 11:28:35
author
arcfide
field
comment
newvalue
I would consider them the same basic issue. It's a literal block escape for scheme values. Why should we limit what goes between them? Arbitrarily limiting them to non space characters is just that, arbitrary. What about \x0;? TAB? I mean, a missing " will capture a whole bunch, and a missing | is no different.
oldvalue
8
raw-time
1269059315000000
ticket
16
time
2010-03-20 11:28:35
Change at time 2010-03-20 11:08:19
author
cowan
field
comment
newvalue
oldvalue
7
raw-time
1269058099000000
ticket
16
time
2010-03-20 11:08:19
Change at time 2010-03-20 11:08:19
author
cowan
field
summary
newvalue
symbol escapes
oldvalue
extended string escapes
raw-time
1269058099000000
ticket
16
time
2010-03-20 11:08:19
Change at time 2010-03-20 11:08:19
author
cowan
field
description
newvalue
[This ticket was originally about string escapes, but commenters have been talking about symbol escapes instead.]
R6RS provides character escapes in symbols of the form `\xnnnn;`, where nnnn is 1-5 hex digits. Do we accept this extension? Do we also allow |...| to escape a whole symbol or a part of one?
oldvalue
R6RS provides an extended string escape syntax,
including the almost ubiquitous \n newline escape,
\xNN; hex escapes, and \<newline> line continuations.
Do we accept any or all of these extensions?
raw-time
1269058099000000
ticket
16
time
2010-03-20 11:08:19
Change at time 2010-03-20 10:54:27
author
cowan
field
comment
newvalue
As far as I'm concerned, it's much more important to be able to import the identifier `FOO` from a case-preserving module into a case-folding one as `|FOO|` rather than `\x46;\x4F;\x4F;`.
oldvalue
6
raw-time
1269057267000000
ticket
16
time
2010-03-20 10:54:27
Change at time 2010-03-20 10:43:01
author
arcfide
field
comment
newvalue
I think the general point of || is to avoid the need for \x20; in the first place.
oldvalue
5
raw-time
1269056581000000
ticket
16
time
2010-03-20 10:43:01
Change at time 2010-03-18 19:55:25
author
cowan
field
comment
newvalue
By "not escaping spaces" I mean that |foo bar| is invalid syntax rather than (as in PLT, Gauche, MIT, Gambit, Chicken, Kawa, SISC, Chez, Ikarus, Scheme 9, Scheme 7) the symbol whose string name is "foo bar". This prevents an unpaired | from turning the rest of the program into a giant symbol, and aids readability as explained in the R6RS rationale. If you want that symbol, write foo\x20;bar or foo\{20}bar or whatever we decide on for local escaping.
oldvalue
4
raw-time
1268916925000000
ticket
16
time
2010-03-18 19:55:25
Change at time 2010-03-18 10:54:52
author
arcfide
field
comment
newvalue
Replying to [comment:2 cowan]:
> Providing |...| escapes for symbols (but not allowing them to escape spaces) deals with much of that.
What do you mean by not allowing |...| to escape spaces?
oldvalue
2.3
raw-time
1268884492000000
ticket
16
time
2010-03-18 10:54:52
Change at time 2010-03-16 11:32:48
author
cowan
field
comment
newvalue
Providing |...| escapes for symbols (but not allowing them to escape spaces) deals with much of that.
oldvalue
2
raw-time
1268713968000000
ticket
16
time
2010-03-16 11:32:48
Change at time 2010-03-16 06:22:33
author
kumoyuki
field
comment
newvalue
The thing is that those escapes make the printable form of symbols *fugly*. At least in Larceny - and as I recall Will explaining it, the Larceny behavior is strongly implied (if not actually mandatory) by R6RS.
I think this area needs work.
oldvalue
1
raw-time
1268695353000000
ticket
16
time
2010-03-16 06:22:33
Change at time 2010-03-16 06:22:33
author
kumoyuki
field
milestone
newvalue
oldvalue
raw-time
1268695353000000
ticket
16
time
2010-03-16 06:22:33