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2.18 Time Parsing and Formatting

Functions are provided to allow parsing strings containing time information and printing time in various formats are available.

Function: extensions:parse-time time-string &key :error-on-mismatch :default-seconds :default-minutes :default-hours :default-day :default-month :default-year :default-zone :default-weekday

parse-time accepts a string containing a time (e.g., "Jan 12, 1952") and returns the universal time if it is successful. If it is unsuccessful and the keyword argument :error-on-mismatch is non-nil, it signals an error. Otherwise it returns nil. The other keyword arguments have the following meaning:

:default-seconds

specifies the default value for the seconds value if one is not provided by time-string. The default value is 0.

:default-minutes

specifies the default value for the minutes value if one is not provided by time-string. The default value is 0.

:default-hours

specifies the default value for the hours value if one is not provided by time-string. The default value is 0.

:default-day

specifies the default value for the day value if one is not provided by time-string. The default value is the current day.

:default-month

specifies the default value for the month value if one is not provided by time-string. The default value is the current month.

:default-year

specifies the default value for the year value if one is not provided by time-string. The default value is the current year.

:default-zone

specifies the default value for the time zone value if one is not provided by time-string. The default value is the current time zone.

:default-weekday

specifies the default value for the day of the week if one is not provided by time-string. The default value is the current day of the week.

Any of the above keywords can be given the value :current which means to use the current value as determined by a call to the operating system.

Function: extensions:format-universal-time dest universal-time @ &key :timezone :style :date-first :print-seconds :print-meridian :print-timezone :print-weekday
Function: extensions:format-decoded-time dest seconds minutes hours day month year @ &key :timezone :style :date-first :print-seconds :print-meridian :print-timezone :print-weekday

format-universal-time formats the time specified by universal-time. format-decoded-time formats the time specified by seconds, minutes, hours, day, month, and year. Dest is any destination accepted by the format function. The keyword arguments have the following meaning:

:timezone

is an integer specifying the hours west of Greenwich. :timezone defaults to the current time zone.

:style

specifies the style to use in formatting the time. The legal values are:

:short

specifies to use a numeric date.

:long

specifies to format months and weekdays as words instead of numbers.

:abbreviated

is similar to long except the words are abbreviated.

:government

is similar to abbreviated, except the date is of the form “day month year” instead of “month day, year”.

:date-first

if non-nil (default) will place the date first. Otherwise, the time is placed first.

:print-seconds

if non-nil (default) will format the seconds as part of the time. Otherwise, the seconds will be omitted.

:print-meridian

if non-nil (default) will format “AM” or “PM” as part of the time. Otherwise, the “AM” or “PM” will be omitted.

:print-timezone

if non-nil (default) will format the time zone as part of the time. Otherwise, the time zone will be omitted.

:print-weekday

if non-nil (default) will format the weekday as part of date. Otherwise, the weekday will be omitted.


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