generate a csv file with date time strings that are easier to sort, from the output of: notmuch show --format=json '*' | jq 'map(.[0][0] | [.headers.Date, .id, .headers.Subject])'

nmj2csv.pl

#!/usr/bin/perl -w

# This script processes the output of:
#      notmuch show --format=json '*' | jq 'map(.[0][0] | [.headers.Date, .id, .headers.Subject])'
# to create a csv file with date time strings that are easier to sort.
use Date::Parse;

while (<>) {
    next unless /"(.*)"/;
    my $item = $1;
    if ($item =~ /(\d+\s+[A-Z][a-z]+\s+(19|20)\d\d\s+\d\d:\d\d:\d\d(\s+[+-]\d+)?)/) {
	@t=strptime($1);
	$yr = $t[5]>=100 ? " " . ($t[5]-100) : "Z$t[5]";
	printf("\n$yr%02d%02d-%02d:%02d:%02d", $t[4]+1, @t[3,2,1,0]);
    } else {
	print(",$item");
    }
}

print("\n");