“用法：文本:: CSV_Xs :: getlineself，io”是什么意思？

问题描述

| 我不是一名程序员，对Perl来说还很陌生。我当前正在编写一个小脚本以从CSV中读取内容，对不同的字段进行一些评估，然后在满足某些条件的情况下打印到另一个文件。我以为我已经完成了很多工作，但是后来我得到了这个新消息：   \“用法：text :: CSV_Xs :: getline（self，io）在date_compare.pl第51行，第3行。” 我一直在尝试寻找可以告诉我此消息含义的内容，但我迷路了。我知道这很简单。我的代码如下。请原谅我的无知。

#! /usr/local/ActivePerl-5.12/bin/perl

#this script will check to files,throw them into arrays and compare them
#to find entries in one array which meet specified criteria
#$field_file is the name of the file that contains the ablation date first,#then the list of compared dates,then the low and high end date criteria,each
#value should end with a \\n.
#$unfiltered_file is the name of the raw CSV with all the data
#$output_file is the name of the file the program will write to
use strict;
use 5.012;
use Text::CSV_XS;
use IO::HANDLE qw/getline/;
use Date::Calc qw/Decode_Date_US2 Delta_Days/;

my $csv = Text::CSV_XS->new ({ binary => 1,eol => $/ }) or
    die \"Cannot use CSV: \".Text::CSV->error_diag ();

my ($field_file,$unfiltered_file,$output_file,@field_list,$hash_keys,%compare,$check,$i);
#Decode_Date_US2 scans a string and tries to parse any date within.
#($year,$month,$day)=Decode_Date_US2($string[,$language])
#Delta_Days returns the difference in days between the two given dates.
#$Dd = Delta_Days($year1,$month1,$day1,$year2,$month2,$day2);
sub days{
    Delta_Days(Decode_Days_US2(@compare{$field_list[0]}),Decode_Days_US2(@compare{$field_list[$i]}));
}

sub printout{
    $csv->print(<OUTPUTF>,$check) or die \"$output_file:\".$csv->error_diag();
}

print \"\\nEnter the check list file name: \";
chomp ($field_file = <STDIN>);
open FIELDF,\"<\",$field_file or die \"$field_file: $!\";
chomp (@field_list=<$field_file>);
close FIELDF or die \"$field_file: $!\";
print \"\\nEnter the raw CSV file name: \";
chomp ($unfiltered_file = <STDIN>);
print \"\\nEnter the output file name : \";
chomp ($output_file = <STDIN>);
open OUTPUTF,\">>\",$output_file or die \"$output_file: $!\";
open RAWF,$unfiltered_file or die \"$unfiltered_file: $!\";
if ($hash_keys = $csv->getline(<RAWF>)){
    $check = $hash_keys;
    &printout();
}else{die \"\\$hash_keys: \".$csv->error_diag();}

while ($check = $csv->getline (<RAWF>)){
    @compare{@$hash_keys}=@$check;    
    TEST: for ($i=1,$i==(@field_list-3),$i++){
        if (&days()>=$field_list[-2] && &days()<=$field_list[-1]){
            last TEST if (&printout());
    }
}    

    

解决方法

Usage: Text::CSV_Xs::getline(self,io) at date_compare.pl line 51,line 3.

getline

显然需要filehandle / IO :: Handle，并且您正在向它传递标量（包含从filehandle读取的行）。 这意味着在您的行上：

if ($hash_keys = $csv->getline(<RAWF>)){

您应该使用：

if ($hash_keys = $csv->getline( \\*RAWF )){

代替。 （但是您实际上应该使用词汇文件句柄，如：）

open FIELDF,\"<\",$field_file or die \"$field_file: $!\";
chomp (@field_list=<$field_file>);       # Not sure how you expect this to work
close FIELDF or die \"$field_file: $!\";

会成为：

open my $fieldf,$field_file or die \"$field_file: $!\";
chomp (@field_list=<$fieldf>);
close $fieldf or die \"$field_file: $!\";