wiki:WG1ChangeSummary

Version 1 (modified by cowan, 6 years ago) (diff)

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This is a very brief summary of what's changed in WG1 relative to R5RS so far:

  • Modules with import, export, begin (for embedded code), include, include-ci, and cond-expand
  • Syntax-rules: ellipsis escaping, SRFI 46, tail patterns, and the _ wildcard
  • Identifiers are case-sensitive
  • Identifiers and other syntax must be delimited with whitespace
  • Extended identifier syntax, including \ and |...| escapes
  • #; and #| ... |# comment styles
  • List of named characters and string esscapes standardized
  • Exception system
  • The only standardized condition is error (with accessors and predicate)
  • Inexact infinities on systems that support them
  • IEEE semantics for transcendental functions
  • Unicode is supported but not required, including folding and normalization
  • Binary I/O
  • String and bytevector ports
  • SRFI 9 records
  • Transcript-on and transcript-off are gone
  • Letrec*, let-values, and let*-values
  • Syntax-error
  • Map, for-each, assoc, and member extended as in SRFI 1
  • Internal define-syntax
  • Bytevectors
  • Support for cyclic list structure as in SRFI 1
  • Read and write cyclic data, with write-simple to suppress writing
  • exact-integer? and exact-integer-sqrt
  • Current-error-port
  • Delete-file and file-exists
  • Finite? and nan? as in R6RS but supporting complex numbers too
  • Command-line, exit, get-environment-variable, get-environment-variables
  • Call/cc
  • SRFI 39 parameters
  • Access to TAI and elapsed time
  • Case-lambda
  • => in case
  • Case folding flags
  • DivisionRiastradh
  • Port?, close-port, and port-closed?
  • Real numbers have #e0 as the imaginary part
  • Nested quasiquotes with partial specification for mutability
  • Procedures need not be tagged with locations
  • Dynamic-wind thunks run in the outer dynamic environment
  • Read-line
  • Physical newline in a string means \n
  • Environment from R6RS
  • Multiple values can be sent to continuations which discard them