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Issue SHARP-O-FOOBAR Writeup

Forum:		Public Review

Issue: SHARP-O-FOOBAR

References: Loosemore's public review comment #5

#b, #o, #x, #r reader syntax

(sections 2.4.8.7 to 2.4.8.10, pages 2-30..2-31)

Category: CLARIFICATION

Edit history: 21 Dec 1992, Version 1 by Loosemore

Status: Proposal CONSEQUENCES-UNDEFINED passed (8+2)-1 on

letter ballot 93-302.

Problem description:

Is #ofoobar valid syntax? In other words, what happens if the

object following #b, #o, #x, or #r doesn't have the syntax of

a rational in the given radix?

Proposal (SHARP-O-FOOBAR:CONSEQUENCES-UNDEFINED):

Clarify that the consequences are undefined if the token following

#b, #o, #x, or #r does not have the syntax of a rational in the given

radix.

Rationale:

At least some implementations signal an error. Other implementations

apparently just rebind *READ-BASE* and call READ recursively.

Current practice:

Lucid, CMU CL, and AKCL all signal an error. WCL reads #ofoobar

as the symbol FOOBAR.

Cost to implementors:

None.

Cost to users:

None, since the behavior already differs among implementations.

Aesthetics:

Being explicitly vague is better than being implicitly vague.

Editorial impact:

Adding one sentence to each of the four referenced sections.

Discussion:


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