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Myoungjin Jeon
Myoungjin Jeon

Posted on • Edited on

[Short Prog] Week Number Getter

#raku #shell #perl #haskell

The one way to store my weekly documents in a directory or a weekly task in a spreadsheet is to store them into a separate directory (or a sheet) by weekly basis. and I used the week number because it has shorter name than using period notation like (08.02-08.08).
I scanned some invoices and name it in sort of "20210805.Chicken.pdf" then I move them into appropriate "week -number-ed" directory.
then I realised that there might be some automatic way to put them into matched weekly directory.

How to get week number in Raku

I'm a raku user. and I could make it a simple terminal interface programme like below.

#!/usr/bin/env raku multi sub MAIN ( Int $year, Int $month, Int $day ) { say Date.new( :$year, :$month, :$day ).week-number(); }
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> chmod u+x week-number.raku > week-number.raku 2021 8 4 31
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I think it's pretty straight forward if get used to some syntax.

If you want to use a single text like "20210804"
I could add one more multi sub for the MAIN()

sub cut-off-last-two-digits( @i ) returns Int { # warning: side effect ( @i.pop, @i.pop ).reverse.join.Int } multi sub MAIN ( Int \yyyymmdd ) { my @i = yyyymmdd.comb; my ( $year, $month, $day ); $day = cut-off-last-two-digits @i; $month = cut-off-last-two-digits @i; $year = @i.join.Int; if (( $year, $month, $day )>>.defined).any == False { die "check your input: {yyyymmdd}"; } samewith( $year, $month, $day ); } multi sub MAIN ( Int $year, Int $month, Int $day ) { say Date.new( :$year, :$month, :$day ).week-number(); }
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Perl5 Version

I searched the internet and I used DateTime module to implement.
but I guess DateTime is quite heavy module. because perl is normally very very fast but this programme isn't.

#!/usr/bin/env perl use strict; use warnings; use v5.26; use DateTime; use File::Basename; our $PROG = $0; my @parsed; my ( $year, $month, $day ); use enum qw(F_YEAR F_MONTH F_DAY); sub usage { print << 'END_OF_USAGE'; $PROG <YYYYMMDD> OR $PROG <YYYY> <MM> <DD> END_OF_USAGE } if ( @ARGV == 1 ) { # parse as YYYYMMDD my $str = $ARGV[0]; @parsed = $str =~ /^(\d+)(\d\d)(\d\d)$/; } elsif ( @ARGV == 3 ) { @parsed = @ARGV; } else { usage(); exit 1; } ( $year, $month, $day ) = @parsed[F_YEAR, F_MONTH, F_DAY]; my $dt = DateTime->new( year => $year, month => $month, day => $day ); print $dt->week_number();
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Haskell Version

I still hate some part of code and there is no proper way to handle errors but it is working fast. so I'm going to stick with this programme for a while.

> stack new week-number
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app/Main.hs 

module Main where import System.Environment import Lib main :: IO () main = do args <- getArgs -- note: args :: [String] putStrLn (case args of yyyymmdd:[] -> weekNumberStringFromString yyyymmdd y:m:d:[] -> let y' = (read y :: Integer) m' = (read m :: Int) d' = (read d :: Int) in weekNumberStringFromGregorian y' m' d' _ -> unlines [ "usage:" , "week-number: <yyyymmdd>" , " or" , "week-number: <yyyy> <m> <d>" ] )
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src/Lib.hs 

module Lib ( weekNumberStringFromString , weekNumberStringFromGregorian ) where import qualified Data.Time as DT weekNumberStringFromString :: String -> String weekNumberStringFromString yyyymmdd = let ut = DT.parseTimeOrError True DT.defaultTimeLocale "%Y%m%d" yyyymmdd :: DT.UTCTime in DT.formatTime DT.defaultTimeLocale "%V" ut weekNumberStringFromGregorian :: Integer -> Int -> Int -> String weekNumberStringFromGregorian y m d = ( DT.formatTime DT.defaultTimeLocale "%V" ) $ DT.fromGregorian y m d
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> stack build > stack install > week-number-exe 2021 8 4 31
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so now I need to make some script go through the file
and get the date information from the file name and move them into
right place.

Okay. That's all today.

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