Print a big string formatted and in multiple lines

alen129 has asked for the wisdom of the Perl Monks concerning the following question:

I have this code in my page print $query->p ("iCAD Detail : $Detail\n"); and this is stored in $Detail variable:

'Sep 30 2016 8:32AM - [2] [Notification] [CHP]-Problem changed from IN
+FO-Information to CLOSURE of a Road by CHP\nSep 30 2016 8:32AM - [1] 
+#2 NB LN CLOSED FROM EL RIVINO TO SANTA ANA\n'
[download]

As you can see it's a mess and very unreadable. Now my question is how do I format it better so it does a newline right before it display the date? something like this:


Sep 30 2016 8:32AM - [2] [Notification] [CHP]-Problem changed from INF
+O-Information to CLOSURE of a Road by CHP\n
[download]

Sep 30 2016 8:32AM - [1] #2 NB LN CLOSED FROM EL RIVINO TO SANTA ANA\n
+'
[download]

The values in $Detail are copied form a database entry.

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Re: Print a big string formatted and in multiple lines by haukex (Archbishop) on Sep 30, 2016 at 17:51 UTC
Hi alen129, Please see How do I post a question effectively? - please use `<code>` tags to format not only your code but your data as well. To convert the string `'\n'` (that is, a literal backslash followed by the letter n) to a newline (perhaps plus something else), you could do `$Detail =~ s/\\n/\n/g; # or $Detail =~ s/\\n/<br>\n/g; # for HTML` [download] Hope this helps, -- Hauke D	[reply] [d/l] [select]
Re^2: Print a big string formatted and in multiple lines by alen129 (Novice) on Sep 30, 2016 at 18:44 UTC
Hauke D, The second line did it for me. Thank you so much. where can I learn more about this sort of string formatting?(what keyword do I search for?)	[reply]
Re^3: Print a big string formatted and in multiple lines by haukex (Archbishop) on Sep 30, 2016 at 19:02 UTC
Hi alen129, `s/\\n/<br>\n/g` is a search-and-replace regular expression, a good place to start is perlretut and perlrequick. Interpolation (`'\n'` vs. `"\n"` vs. `"\\n"`) is discussed in a few different places, for example a bit in Scalar value constructors and Quote and Quote like Operators. Also, as mentioned as one of the points in the Basic debugging checklist, it's probably a good habit to get into to use a module like Data::Dumper or Data::Dump to look at the content your variables: `my $Detail = 'Sep 30 2016 8:32AM CHP\nSep 30 2016 8:32AM SANTA ANA\n'; use Data::Dumper; $Data::Dumper::Useqq=1; print Dumper $Detail; # - or - use Data::Dump 'dump'; print dump $Detail;` [download] Both will unambiguously show you the content of the string in Perl's syntax, for example `"Sep 30 2016 8:32AM CHP\\nSep 30 2016 8:32AM SANTA ANA\\n"`. Hope this helps, -- Hauke D	[reply] [d/l] [select]