Issue ARGUMENTS-UNDERSPECIFIED Writeup

Issue:        ARGUMENTS-UNDERSPECIFIED

References:   LOGBITP (p 224), MAKE-DISPATCH-MACRO-CHARACTER (p 363), 

              MAKE-HASH-TABLE (p 283), MAKE-SEQUENCE (p 249), READ (p 375)

              MAKE-STRING (p 302), NTHCDR (p 267), PARSE-INTEGER (p 381),

              SET (p 92)

              Issue: RANGE-OF-START-END-PARAMETERS.

Category:     CLARIFICATION

Edit history: 26-Aug-88, Version 1 by Chapman

               4-Sep-88, version 2 by Masinter

              19-Sept-88, Version 3 by Chapman

              21-Sep-88, Version 4 by Masinter

 

Problem Description:

 

The descriptions of LOGBITP, MAKE-DISPATCH-MACRO-CHARACTER, READ, SET,

MAKE-HASH-TABLE, MAKE-SEQUENCE, MAKE-STRING, NTHCDR, and PARSE-INTEGER 

are not clear about the types of the arguments supplied to these 

constructs.

 

Proposal (ARGUMENTS-UNDERSPECIFIED:SPECIFY)

 

Clarify that the arguments for the listed constructs are as follows:

 

Construct                Argument	                 Type

LOGBITP                   index		      non-negative integer

MAKE-DISPATCH-MACRO-CHARACTER 	char		      character

MAKE-HASH-TABLE            size	 	      non-negative integer

MAKE-SEQUENCE              size		      non-negative integer

MAKE-SEQUENCE              type		      type specifier

MAKE-STRING                size                non-negative integer

MAKE-STRING                initial-element	 string-char

NTHCDR                     n		           non-negative integer

SET-SYNTAX-FROM-CHAR       to-char,from-char   characters

READ and others            eof-value	      any value

SET                        value		      any value

 

(MAKE-HASH-TABLE, MAKE-SEQUENCE, MAKE-STRING have additional constraints on

their respective SIZE arguments; for example, MAKE-STRING may detect an error if

SIZE is greater than or equal to ARRAY-DIMENSION-LIMIT. Some additional 

restriction on the range of characters which can have syntax in readtables 

and are allowable to MAKE-DISPATCH-MACRO-CHARACTER SET-SYNTAX-FROM-CHAR might

be required in some other proposal.)

 

Rationale:

 

This clarification allows predictible results to occur when 

arguments are supplied to these constructs.

 

Current Practice:


This proposal seems to be in line with current implementations.


Cost to Implementors:

 

None, since this is consistent with current practice.

 

Cost to Users:

None, since this is consistent with current practice.

 

Benefits:

 

This clarification will assist users in writing portable code.

 

Aesthetics:

 

The standard would be less clean were the allowed ranges of its functions not

specified.

 

Discussion:


There is a separate cleanup proposal RANGE-OF-START-END-PARAMETERS which

addresses a possible incompatible change. This proposal contains what we

think are non-controversial clarifications.