strptime("%Y-%m") in perl6

leszekdubiel has asked for the wisdom of the Perl Monks concerning the following question:

I decided to give a try to perl6 and I got stuck -- how to parse date in format %Y-%m? Year and month only...?

perl6 -e  'say Date.new("2019-01-20"); say Date.new("2019-01"); '
2019-01-20
Invalid Date string '2019-01'; use yyyy-mm-dd instead
  in block <unit> at -e line 1
[download]

Edit Let's say I want to check if month is valid. In perl 5 it is so simple:


use Time::Piece; localtime()->strptime(@ARGV[0], "%Y-%m");
[download]

I don't care about date parsing, I don't look at string at all -- perl5 does that for me.


bash$    perl -e 'use Time::Piece; localtime()->strptime(@ARGV[0], "%Y
+-%m"); print "ok\n"; '  "2019-01"
ok


bash$    perl -e 'use Time::Piece; localtime()->strptime(@ARGV[0], "%Y
+-%m"); print "ok\n"; '  "2019-77"
Error parsing time at /usr/lib/x86_64-linux-gnu/perl/5.26/Time/Piece.p
+m line 481.
[download]

What is elegant way to do thatn in perl6?

Comment on strptime("%Y-%m") in perl6 Select or Download Code

Replies are listed 'Best First'.
Re: strptime("%Y-%m") in perl6 by choroba (Cardinal) on Feb 05, 2019 at 08:53 UTC
Use the named parameters: `say Date.new(year => 2019, month => 1);` [download] I don't see any other signature where the missing day would pass: `multi method new($year, $month, $day, :&formatter --> Date:D) multi method new(:$year!, :$month = 1, :$day = 1 --> Date:D) multi method new(Str $date --> Date:D) multi method new(Instant:D $dt --> Date:D) multi method new(DateTime:D $dt --> Date:D)` [download] `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re: strptime("%Y-%m") in perl6 by Laurent_R (Canon) on Feb 05, 2019 at 12:22 UTC
choroba has provided a good solution. Depending on what you need exactly, this is another possible solution using a formatter (demonstrated here on the REPL): > my $fmt = { sprintf "%04d-%02d", .year, .month }; -> ;; $_? is raw { #`(Block\|173600432) ... } > say Date.new(2019, 1, 1, formatter => $fmt); 2019-01 [download] Update: Please note that you don't need to predefine the formatter: `> say Date.new(2019, 1, "1", formatter => { sprintf "%04d-%02d", .year +, .month }) 2019-01` [download]	[reply] [d/l] [select]
Re^2: strptime("%Y-%m") in perl6 by leszekdubiel (Scribe) on Feb 05, 2019 at 14:01 UTC
Let's say I want to check if month is valid. In perl 5 it is so simple: `use Time::Piece; localtime()->strptime(@ARGV[0], "%Y-%m");` [download] I don't care about date parsing, I don't look at string at all -- perl5 does that for me. `bash$ perl -e 'use Time::Piece; localtime()->strptime(@ARGV[0], "%Y +-%m"); print "ok\n"; ' "2019-01" ok bash$ perl -e 'use Time::Piece; localtime()->strptime(@ARGV[0], "%Y +-%m"); print "ok\n"; ' "2019-77" Error parsing time at /usr/lib/x86_64-linux-gnu/perl/5.26/Time/Piece.p +m line 481.` [download] What is elegant way to do thatn in perl6?	[reply] [d/l] [select]
Re^3: strptime("%Y-%m") in perl6 by choroba (Cardinal) on Feb 05, 2019 at 14:55 UTC
But also `$ perl -MTime::Piece -le 'localtime()->strptime(shift, "%Y-%m-%d"); pr +int "ok"' 2019-02-30 ok` [download] `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re^3: strptime("%Y-%m") in perl6 by Laurent_R (Canon) on Feb 05, 2019 at 17:04 UTC
Nor sure to really understand your requirement, but what about this: `> for <1 5 3 13> -> $month { say Date.new(2019, $month, 1 )} 2019-01-01 2019-05-01 2019-03-01 Month out of range. Is: 13, should be in 1..12 in block <unit> at <unknown file> line 1` [download]	[reply] [d/l]
Re^4: strptime("%Y-%m") in perl6 by leszekdubiel (Scribe) on Feb 05, 2019 at 17:34 UTC
Re^5: strptime("%Y-%m") in perl6 by Laurent_R (Canon) on Feb 05, 2019 at 20:17 UTC


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