hledger-lib-0.23.3: Core data types, parsers and utilities for the hledger accounting tool.

Safe HaskellNone




Date parsing and utilities for hledger.

For date and time values, we use the standard Day and UTCTime types.

A SmartDate is a date which may be partially-specified or relative. Eg 2008/12/31, but also 2008/12, 12/31, tomorrow, last week, next year. We represent these as a triple of strings like ("2008","12",""), ("","","tomorrow"), ("","last","week").

A DateSpan is the span of time between two specific calendar dates, or an open-ended span where one or both dates are unspecified. (A date span with both ends unspecified matches all dates.)

An Interval is ledger's "reporting interval" - weekly, monthly, quarterly, etc.


Misc date handling utilities

getCurrentDay :: IO Day Source

Get the current local date.

getCurrentMonth :: IO Int Source

Get the current local month number.

getCurrentYear :: IO Integer Source

Get the current local year.

spanContainsDate :: DateSpan -> Day -> Bool Source

Does the span include the given date ?

parsedateM :: String -> Maybe Day Source

Parse a couple of date string formats to a time type.

parsedate :: String -> Day Source

Parse a date string to a time type, or raise an error.

parsePeriodExpr :: Day -> String -> Either ParseError (Interval, DateSpan) Source

Parse a period expression to an Interval and overall DateSpan using the provided reference date, or return a parse error.

spansSpan :: [DateSpan] -> DateSpan Source

Get overall span enclosing multiple sequentially ordered spans.

spanIntersect :: DateSpan -> DateSpan -> DateSpan Source

Calculate the intersection of two datespans.

spansIntersect :: [DateSpan] -> DateSpan Source

Calculate the intersection of a number of datespans.

spanDefaultsFrom :: DateSpan -> DateSpan -> DateSpan Source

Fill any unspecified dates in the first span with the dates from the second one. Sort of a one-way spanIntersect.

spanUnion :: DateSpan -> DateSpan -> DateSpan Source

Calculate the union of two datespans.

spansUnion :: [DateSpan] -> DateSpan Source

Calculate the union of a number of datespans.

smartdate :: GenParser Char st SmartDate Source

Parse a date in any of the formats allowed in ledger's period expressions, and maybe some others:

october, oct
yesterday, today, tomorrow
this/next/last week/day/month/quarter/year

Returns a SmartDate, to be converted to a full date later (see fixSmartDate). Assumes any text in the parse stream has been lowercased.

splitSpan :: Interval -> DateSpan -> [DateSpan] Source

Split a DateSpan into one or more consecutive whole spans of the specified length which enclose it. If no interval is specified, the original span is returned.

fixSmartDate :: Day -> SmartDate -> Day Source

Convert a SmartDate to an absolute date using the provided reference date.

fixSmartDateStr :: Day -> String -> String Source

Convert a smart date string to an explicit yyyy/mm/dd string using the provided reference date, or raise an error.

fixSmartDateStrEither :: Day -> String -> Either ParseError String Source

A safe version of fixSmartDateStr.

daysInSpan :: DateSpan -> Maybe Integer Source

Count the days in a DateSpan, or if it is open-ended return Nothing.

mkdatespan :: String -> String -> DateSpan Source

Make a datespan from two valid date strings parseable by parsedate (or raise an error). Eg: mkdatespan "201111" "20111231".