Perl Datetime::Format::ISO8601问题

Question

我搞不懂为什么这会给我“无效的日期格式: 2021-09-10”，这是我的代码：

use DateTime;
use DateTime::Span;
use Datetime::Format::ISO8601;
open(FH_Comp, "<", "C:\\Perl_Scripts\\Stock_List_COMPARE.txt") or die("Cannot open Stock_List_COMPARE.txt: $!\n"); 
my @lines = <FH_Comp>; 
close(FH_Comp);

open(FH_CompRev, "<", "C:\\Perl_Scripts\\Stock_List_Rev.txt") or die("Cannot open Stock_List_Rev.txt: $!\n"); 
my @compRev = <FH_CompRev>; 
close(FH_CompRev);
    
my $iso8601 = DateTime::Format::ISO8601->new;

foreach $lines (@lines) {
    @COMPlist = split(",",$lines);
    foreach $compRev (@compRev) {       
        @REVlist = split(",",$compRev);
        my $dt_set = DateTime::Span->from_datetimes(
            start  => $iso8601->parse_datetime($REVlist[0]),
            before => $iso8601->parse_datetime($REVlist[4]),
        );          
        if ( $dt_set->contains( $iso8601->parse_datetime($COMPlist[0]) ) ) {    
            print "Within date range\n";
            $Total1 = $COMPlist[2] + $REVlist[2];
            print "ADJ Date is '$COMPlist[0]' => $COMPlist[2] + $REVlist[2] = " . $Total1 . " ! '$REVlist[0]' or '$REVlist[4]'";        
        }
        else {
            print "Not within date range\n";
        }           
    }
}

下面是Stock_List_COMPARE.txt的样子：

2016-06-30, 00354                          , 1.00000, 38.62000
2016-06-30, 00354                          , 24.00000, 38.62000

下面是Stock_List_Rev.txt的外观：

2021-09-10,  00354                         , 1.00000, 44.44000, 2021-09-10
2021-08-27,  00354                         , 2.00000, 44.24000, 2021-09-10

奇怪的是，如果它是硬编码的，而不是从我的文件中获得它，为什么它还能工作(参见下面的代码)：

use DateTime;
use DateTime::Span;
use Datetime::Format::ISO8601;
    my $iso8601t = DateTime::Format::ISO8601->new;
    my $first = "2020-12-10"; 
    my $last = "2021-09-10";
    #chomp $last;
    my $dt_set = DateTime::Span->from_datetimes(
        start  => $iso8601t->parse_datetime($first),
        before => $iso8601t->parse_datetime($last),
    );
    if ( $dt_set->contains( $iso8601t->parse_datetime("2021-04-10") ) ) {   
        print "Within date range\n";
    }
    else {
        print "Not within date range\n";
    } 

提前感谢！

Answer 1

请看更正后的代码，OP的问题是日期没有经过清理，并且包含空格和新行。

函数split采用非常灵活的正则表达式形式的分隔符，这在这种情况下非常有用

注意：

• OP必须以use strict;和use warnings;开始代码，否则一些不受欢迎的行为可能会在

中出现

• OP用my $variable;声明了一些变量，但其他变量没有声明--在代码中的某个地方，他/她很可能会在局部作用域中重新定义一个变量，这会导致意外行为

use strict;
use warnings;

use DateTime;
use DateTime::Span;
use Datetime::Format::ISO8601;

my $fn_compare = 'C:\Perl_Scripts\Stock_List_COMPARE.txt';
my $fn_rev     = 'C:\Perl_Scripts\Stock_List_Rev.txt';

open(FH_Comp, "<", $fn_compare) or die("Cannot open $fn_compare: $!"); 
my @lines = <FH_Comp>; 
close(FH_Comp);

open(FH_CompRev, "<", $fn_rev) or die("Cannot open $fn_rev: $!"); 
my @compRev = <FH_CompRev>; 
close(FH_CompRev);
    
my $iso8601 = DateTime::Format::ISO8601->new;

foreach my $line (@lines) {
    my @COMPlist = split('[,\s]+',$line);
    foreach my $compRev (@compRev) {       
        my @REVlist = split('[,\s]+',$compRev);
        my $dt_set = DateTime::Span->from_datetimes(
            start  => $iso8601->parse_datetime($REVlist[0]),
            before => $iso8601->parse_datetime($REVlist[4]),
        );          
        if ( $dt_set->contains( $iso8601->parse_datetime($COMPlist[0]) ) ) {    
            print "Within date range\n";
            my $Total1 = $COMPlist[2] + $REVlist[2];
            print "ADJ Date is '$COMPlist[0]' => $COMPlist[2] + $REVlist[2] = " . $Total1 . " ! '$REVlist[0]' or '$REVlist[4]'";        
        }
        else {
            print "Not within date range\n";
        }           
    }
}

输出

Not within date range
Not within date range
Not within date range
Not within date range

注意:也许OP可以使用my($var_1,$var_2,$var_3,$var_4) = split('[,\s]+',$line);来分配更有意义的变量名，以使代码更具可读性和更易于维护

注意:请查看以下代码样式是否对您有意义

        if ( $dt_set->contains( $iso8601->parse_datetime($COMPlist[0]) ) ) {    
            print "Within date range\n";
            printf "ADJ Date is %s => %s + %s = %s ! %s or %s\n",
                   $COMPlist[0],
                   $COMPlist[2],
                   $REVlist[2],
                   $COMPlist[2] + $REVlist[2],
                   $REVlist[0],
                   $REVlist[4];        
        } else {
            print "Not within date range\n";
        }           

注意：print "$var\n";可以替换为say $var; --在代码文件的顶部添加use feature 'say';行

参考：say