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Source for ticket #65

cc

changetime

2012-10-05 00:51:19

component

WG1 - Core

description

R5RS requires that Scheme support five indicators for the precision of floating-point values, not only the default `e` but also `s`, `f`, `d`, and `l`.  Only a few Schemes actually support more than one precision, so this is mostly noise.  Shall we make it an optional feature?

id

keywords

milestone

owner

alexshinn

priority

major

reporter

cowan

resolution

fixed

severity

status

closed

summary

Precision indicators

time

2010-05-03 11:59:41

type

defect

Changes

Change at time 2012-10-05 00:51:19

author

cowan

field

comment

newvalue

oldvalue

raw-time

1349373079439845

ticket

time

2012-10-05 00:51:19

Change at time 2012-10-05 00:51:19

author

cowan

field

resolution

newvalue

fixed

oldvalue

raw-time

1349373079439845

ticket

time

2012-10-05 00:51:19

Change at time 2012-10-05 00:51:19

author

cowan

field

status

newvalue

closed

oldvalue

writing

raw-time

1349373079439845

ticket

time

2012-10-05 00:51:19

Change at time 2011-03-03 23:51:32

author

cowan

field

comment

newvalue

The "may"s in 6.2.4 are not RFC 2119; they express what the user can do to achieve a certain result.  Since the purpose of a standard is to define the agreement between users and implementers, the whole thing should be recast in terms of what implementations MUST, SHOULD, or MAY do.  I just filed a ticket for RFC 2119 compliance.

Here's my suggestion:

In systems with inexact numbers of varying precisions it may be useful to specify the precision of a constant. For this purpose, implementations MAY accept numerical constants written with an exponent marker s, f, d, or l in place of e.  The effect of these markers is implementation-defined.

oldvalue

raw-time

1299167492000000

ticket

time

2011-03-03 23:51:32

Change at time 2011-03-03 23:19:41

author

alexshinn

field

comment

newvalue

There's nothing in particular to change here - the standard
already states:

    Although Scheme allows a variety of written notations for
    numbers, any particular implementation may support only
    some of them.

I considered making the optionality more clear in the section
on precision indicators, but it already uses "may" for everything.
But it's a lot of text for something almost all implementations
ignore - suggestions welcome.

oldvalue

raw-time

1299165581000000

ticket

time

2011-03-03 23:19:41

Change at time 2011-03-03 23:00:55

author

alexshinn

field

comment

newvalue

oldvalue

raw-time

1299164455000000

ticket

time

2011-03-03 23:00:55

Change at time 2011-03-03 23:00:55

author

alexshinn

field

owner

newvalue

alexshinn

oldvalue

raw-time

1299164455000000

ticket

time

2011-03-03 23:00:55

Change at time 2011-03-03 23:00:55

author

alexshinn

field

status

newvalue

writing

oldvalue

decided

raw-time

1299164455000000

ticket

time

2011-03-03 23:00:55

Change at time 2011-01-29 11:22:33

author

alexshinn

field

comment

newvalue

oldvalue

raw-time

1296271353000000

ticket

time

2011-01-29 11:22:33

Change at time 2011-01-29 11:22:33

author

alexshinn

field

status

newvalue

decided

oldvalue

assigned

raw-time

1296271353000000

ticket

time

2011-01-29 11:22:33

Change at time 2011-01-29 11:22:23

author

alexshinn

field

comment

newvalue

oldvalue

raw-time

1296271343000000

ticket

time

2011-01-29 11:22:23

Change at time 2011-01-29 11:22:23

author

alexshinn

field

owner

newvalue

oldvalue

alexshinn

raw-time

1296271343000000

ticket

time

2011-01-29 11:22:23

Change at time 2011-01-29 11:22:23

author

alexshinn

field

status

newvalue

assigned

oldvalue

reopened

raw-time

1296271343000000

ticket

time

2011-01-29 11:22:23

Change at time 2011-01-29 11:22:11

author

alexshinn

field

comment

newvalue

oldvalue

raw-time

1296271331000000

ticket

time

2011-01-29 11:22:11

Change at time 2011-01-29 11:22:11

author

alexshinn

field

resolution

newvalue

oldvalue

fixed

raw-time

1296271331000000

ticket

time

2011-01-29 11:22:11

Change at time 2011-01-29 11:22:11

author

alexshinn

field

status

newvalue

reopened

oldvalue

closed

raw-time

1296271331000000

ticket

time

2011-01-29 11:22:11

Change at time 2010-10-18 02:41:19

author

cowan

field

comment

newvalue

oldvalue

raw-time

1287344479000000

ticket

time

2010-10-18 02:41:19

Change at time 2010-10-18 02:41:19

author

cowan

field

resolution

newvalue

fixed

oldvalue

raw-time

1287344479000000

ticket

time

2010-10-18 02:41:19

Change at time 2010-10-18 02:41:19

author

cowan

field

status

newvalue

closed

oldvalue

new

raw-time

1287344479000000

ticket

time

2010-10-18 02:41:19

Change at time 2010-10-18 02:40:44

author

cowan

field

comment

newvalue

The WG voted to make the precision indicators optional.

oldvalue

raw-time

1287344444000000

ticket

time

2010-10-18 02:40:44