GBBopen 1.5 Reference -- parse-date

parse-date

parse-date string &key start end junk-allowed separators month-precedes-date year-first default-to-current-year => date, month, year, position [Function]

Purpose
Parse a date-specification string.

Package :gbbopen-tools (home package is :module-manager)

Module :module-manager

Arguments and values

string		A simple string
start		Starting index into `string` (default is `0`)
end		Ending index into `string` (default is `nil`, meaning end of `string`)
junk-allowed		A generalized boolean (default is `nil`)
separators		A sequence of characters that are skipped and separate the date, month, and year fields in `string`, if needed (default is `"-/ ,"`)
month-precedes-date		A generalized boolean (default is *month-precedes-date*)
year-first		A generalized boolean (default is *year-first*)
default-to-current-year		A generalized boolean (default is `nil`)
date		An integer between 1 and up to 31, inclusive, depending on the month and year
month		An integer between 1 and 12, inclusive
year		An integer
position		A index in `string`

Returns
Four values: date, month, year, and position

Errors
If junk-allowed is false, an error is signaled if a numeric field in string does not consist entirely of the representation of a integer, possibly surrounded on either side by characters in separators.

Description
Both the month and date must be specified in string, optionally followed by the year and the time of day. The month can be a numeric value (1–12), a three-letter abbreviation, or the full month name. If the month is specified numerically, then the value of month-precedes-date is used to determine the month and date ordering. If no year is specified in string and default-to-current-year is nil, the current calendar year is assumed, unless the specified month and date have passed, in which case the next year is assumed. If no year is specified in string and default-to-current-year is true, the current calendar year is always assumed.

The returned position is the index within string where the parse ended.

Examples

  > (parse-date "1 Apr 2010")
  1
  4
  2010
  10
  > (parse-date "April 1, 2010")
  1
  4
  2010
  13
  > (parse-date "Thu 1 Apr 2010")
  1
  4
  2010
  14
  > (parse-date "Thursday, April 1, 2010")
  1
  4
  2010
  23
  > (parse-date "1-4-10" :month-precedes-date 't)
  4
  1
  2010
  6
  > (parse-date "1-4-10" :month-precedes-date nil)
  1
  4
  2010
  6
  > (parse-date "1-4-10" :month-precedes-date 't :year-first 't)
  10
  4
  2001
  6
  > (parse-date "1-4-10" :month-precedes-date nil :year-first 't)
  4
  10
  2001
  6
  > (parse-date "4 Jul") ;; entered May 1, 2008
  4
  7
  2008
  5
  > (parse-date "4 Jul") ;; entered August 1, 2008
  4
  7
  2009
  5
  > (parse-date "4 Jul"  ;; entered August 1, 2008
      :default-to-current-year 't)
  4
  7
  2008
  5
  > (parse-date "4/7  " :month-precedes-date nil)
  4
  7
  2008
  5
  > (parse-date "4/7  junk" :junk-allowed 't)
  7
  4
  2008
  5
  >

Note
This function is loaded with the :module-manager module in order to to make it available as early as possible.

The GBBopen Project

parse-date