Re: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play.

As documented in perlop, the substitution

> Searches a string for a pattern, and if found, replaces that pattern with the replacement text and returns the number of substitutions made.

Your s/// replaced once, so it returned 1. Run the substitution before printing the result.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

Comment on Re: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. Download Code

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Re^2: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. by perlynewby (Scribe) on Oct 16, 2020 at 19:25 UTC
Yes, this is what I did not understand that replacing the space to no space would return 1. I went I did a few experiments to solidify my understanding. I spent so much time reading but could not understand the inner workings; I appreciate it so much.	[reply]
Re^3: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. by haukex (Archbishop) on Oct 16, 2020 at 20:40 UTC
Maybe this table of the return values of regular expressions can be helpful as well.	[reply]
Re^2: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. by ikegami (Patriarch) on Oct 17, 2020 at 18:22 UTC
Run the substitution before printing the result. ...or use `s///r`	[reply] [d/l]
Re^3: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. by Anonymous Monk on Oct 17, 2020 at 21:39 UTC
...or use s///r not what OP wants	[reply]
Re^4: One liner is returning unexpected "1" on the output and I do not understand the mechanism at play. by ikegami (Patriarch) on Oct 17, 2020 at 22:00 UTC
Yes it is. They asked to "print line with no leading space" instead of "1". This can be achieved by replacing `print s/^\s+//, ...; # This is printing 1` [download] with `print s/^\s+//r, ...;` [download]	[reply] [d/l] [select]


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