1 Installed Patch Level
patchlevel
2 Checking Available Versions
check-version
3 Dr Scheme Version Tool
4 Version Utilities
valid-version?
version->list
version<?
version<=?
alpha-version?
version->integer
Version: 4.2.1

Version: PLT Version Checking

The version collection contains several version-related pieces that are used by PLT Scheme. See also version from scheme/base.

1 Installed Patch Level

 (require version/patchlevel)

Indicates the current installed patch level, which is normally zero, but may be updated by patches to DrScheme.

2 Checking Available Versions

 (require version/check)

Checks the currently available version on the PLT website (http://download.plt-scheme.org) and returns a value that indicates the current state of the curent installation:

3 DrScheme Version Tool

 (require version/tool)

The version/tool library implements a DrScheme tool that

4 Version Utilities

The version/utils library provides a few of convenient utilities for dealing with version strings. Unless explicitly noted, these functions do not handle legacy versions of PLT Scheme.

(valid-version? str)  boolean?
  str : string?
Returns #t if str is a valid PLT Scheme version string, #f otherwise.

Returns a list of four numbers that the given version string represent. str is assumed to be a valid version.

(version<? str1 str2)  boolean?
  str1 : valid-version?
  str2 : valid-version?
Returns #t if str1 represents a version that is strictly smaller than str2, #f otherwise. str1 and str2 are assumed to be valid versions.

(version<=? str1 str2)  boolean?
  str1 : valid-version?
  str2 : valid-version?
Returns #t if str1 represents a version that is smaller than or equal to str2, #f otherwise. str1 and str2 are assumed to be valid versions.

(alpha-version? str)  boolean?
  str : valid-version?
Returns #t if the version that str represents is an alpha version. str is assumed to be a valid version.

(version->integer str)  (or/c integer? false/c)
  str : string?
Converts the version string into an integer. For version "X.YY.ZZZ.WWW", the result will be XYYZZZWWW. This function works also for legacy PLT Scheme versions, by translating "XYY.ZZZ" to XYYZZZ000. The resulting integer can thefore be used to conveniently compare any two (valid) version strings. If the version string is invalid the resulting value is #f.

Note that this is the only function that deals with legacy version strings.