Opened 7 years ago

Closed 5 years ago

#12 closed defect (fixed)

symbol literal extensions

Reported by: alexshinn Owned by: alexshinn
Priority: major Milestone:
Component: WG1 - Reader Syntax Keywords:
Cc:

Description

R6RS added exceptions for symbols beginning with
"->". Do we accept this, or allow even more
symbols?

Change History (9)

comment:1 Changed 7 years ago by cowan

My sense was that most R5RS systems accept anything as an identifier that doesn't parse as a number. Here's what I found using '(+on+ 4bsd -off-):

PLT, Gauche, MIT, Gambit, Chicken, Bigloo, scsh, Scheme 9, Scheme 7, VSCM are okay with it.

Scheme48, Ikarus, Larceny, SSCM, SXM, Chibi report lexical syntax errors.

I don't know of any Scheme that supports extensions to the R5RS/R6RS syntax of numbers that would make these identifiers a problem. I recommend that we allow them.

comment:2 Changed 7 years ago by alexshinn

Chibi accepts +on+ and -off-, it just doesn't allow
symbols beginning with digits. It seems much more
likely that someone started to write a number and
got a suffix wrong. For instance, you propose 4bsd
as a symbol, but 4d0 is valid R5RS numeric syntax.

comment:3 Changed 6 years ago by cowan

WG1 accepted Alex Shinn's proposal.

comment:4 Changed 6 years ago by cowan

  • Resolution set to fixed
  • Status changed from new to closed

that is, symbols may not begin with a number prefix

comment:5 Changed 6 years ago by alexshinn

  • Resolution fixed deleted
  • Status changed from closed to reopened

comment:6 Changed 6 years ago by alexshinn

  • Owner alexshinn deleted
  • Status changed from reopened to assigned

comment:7 Changed 6 years ago by alexshinn

  • Status changed from assigned to decided

comment:8 Changed 6 years ago by alexshinn

  • Owner set to alexshinn
  • Status changed from decided to writing

comment:9 Changed 5 years ago by cowan

  • Resolution set to fixed
  • Status changed from writing to closed
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