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Source for ticket #388

cc


    
changetime

    
2012-10-07 12:18:45

    
component

    
WG1 - Core

    
description

    
Currently we don't specify what `display` does with circular lists.  Should it generate labels like `write`, or loop like `write-simple`, or leave it unspecified?

    
id

    
388

    
keywords

    

    
milestone

    

    
owner

    
cowan

    
priority

    
major

    
reporter

    
cowan

    
resolution

    
fixed

    
severity

    

    
status

    
closed

    
summary

    
Specify what `display` does with circular lists

    
time

    
2012-05-03 07:08:32

    
type

    
defect

    
Changes

    
Change at time 2012-10-07 12:18:45

    
author

    
cowan

    
field

    
comment

    
newvalue

    

    
oldvalue

    
5

    
raw-time

    
1349587125055128

    
ticket

    
388

    
time

    
2012-10-07 12:18:45

    
Change at time 2012-10-07 12:18:45

    
author

    
cowan

    
field

    
resolution

    
newvalue

    
fixed

    
oldvalue

    

    
raw-time

    
1349587125055128

    
ticket

    
388

    
time

    
2012-10-07 12:18:45

    
Change at time 2012-10-07 12:18:45

    
author

    
cowan

    
field

    
status

    
newvalue

    
closed

    
oldvalue

    
writing

    
raw-time

    
1349587125055128

    
ticket

    
388

    
time

    
2012-10-07 12:18:45

    
Change at time 2012-08-27 06:23:30

    
author

    
cowan

    
field

    
comment

    
newvalue

    

    
oldvalue

    
4

    
raw-time

    
1346023410646797

    
ticket

    
388

    
time

    
2012-08-27 06:23:30

    
Change at time 2012-08-27 06:23:30

    
author

    
cowan

    
field

    
owner

    
newvalue

    
cowan

    
oldvalue

    
alexshinn

    
raw-time

    
1346023410646797

    
ticket

    
388

    
time

    
2012-08-27 06:23:30

    
Change at time 2012-08-27 06:23:30

    
author

    
cowan

    
field

    
status

    
newvalue

    
writing

    
oldvalue

    
decided

    
raw-time

    
1346023410646797

    
ticket

    
388

    
time

    
2012-08-27 06:23:30

    
Change at time 2012-08-26 23:12:30

    
author

    
cowan

    
field

    
comment

    
newvalue

    
WG1 decided to adopt `write` behavior, printing datum labels as required.

    
oldvalue

    
3

    
raw-time

    
1345997550677653

    
ticket

    
388

    
time

    
2012-08-26 23:12:30

    
Change at time 2012-08-26 23:12:30

    
author

    
cowan

    
field

    
status

    
newvalue

    
decided

    
oldvalue

    
new

    
raw-time

    
1345997550677653

    
ticket

    
388

    
time

    
2012-08-26 23:12:30

    
Change at time 2012-05-06 22:50:14

    
author

    
cowan

    
field

    
comment

    
newvalue

    
If you compare `write`, `write-simple`, and `display`, you'll see that `write` defines behavior for strings, symbols, characters, and shared structure.  `Write-simple` says it is the same as `write` except on shared structure.  However, `display` defines behavior for strings, symbols, and characters only.  Adding a definition for shared-list behavior is therefore appropriate.  We don't need to define behavior for everything else.

I haven't done a full test, but most Schemes seem to use `write-simple` behavior.

    
oldvalue

    
2

    
raw-time

    
1336319414823298

    
ticket

    
388

    
time

    
2012-05-06 22:50:14

    
Change at time 2012-05-06 17:24:35

    
author

    
alexshinn

    
field

    
comment

    
newvalue

    
We don't specify anything wrt display for anything
other than string and character inputs.  It would be
very out of place to specify anything for circular
structures without also specifying all structures,
which would be very difficult to get implementations
to agree to.

    
oldvalue

    
1

    
raw-time

    
1336299875204900

    
ticket

    
388

    
time

    
2012-05-06 17:24:35