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Date-literals

A reader extension providing SRFI-19 date/time literals of the form #@2007-12-31T23:59:59Z.

Examples

Using date/time literals in the interpreter

Loading date-literals also loads srfi-19 and allows using date/time literals as follows:

#;1> (use date-literals)

#;2> (current-date)
#@2007-03-26T09:55:54Z

#;3> #@2007-12-31T23:59:59Z
#@2007-12-31T23:59:59Z

#;4> ,d #@2007-12-31
structure of type `date'
...

#;5> ,x #@2007-12-31
(make-date 0 0 0 0 31 12 2007 7200)

Using date/time literals with the compiler

Passing a -X date-literals command-line option to csc allows you to conveniently make use of date/time literals in your egg or compiled program without making the date-literals egg a runtime dependency.

Author

Arto Bendiken

Requires

Reader extensions

This egg installs a reader extension for #\@ that reads a date/time literal as described below in read-date-literal. Additionally, a record printer is installed so that all SRFI-19 date objects are automatically printed using write-date-literal.

Note that there are some caveats to using reader extensions when compiling; for more details, refer to the relevant FAQ entry.

Input and output

read-date-literal

(read-date-literal [PORT]) procedure

Reads a date/time literal from PORT, which defaults to the value of (current-input-port). The literal is converted to an SRFI-19 date using the first matching format template as follows:

  • #@~Y-~m-~dT~H:~M:~S~z
  • #@~Y-~m-~dT~H:~M:~S
  • #@~Y-~m-~d

write-date-literal

(write-date-literal DATE [PORT]) procedure

Writes the SRFI-19 date object DATE in #@~Y-~m-~dT~H:~M:~S~z format to PORT, which defaults to the value of (current-output-port).

License

 Copyright (c) 2006-2007 Arto Bendiken.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to
 deal in the Software without restriction, including without limitation the
 rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 sell copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 IN THE SOFTWARE.

Version history

1.0.2
Renamed the exported procedures for greater sanity.
1.0.1
Renamed the egg to date-literals and made it compilable.
1.0.0
Initial release of date-syntax egg for use in the interpreter.

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