Remove comments from many files

In older versions of Rust when we created a new crate using cargo new it added a comment to the generated Cargo.toml file:

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

On one hand this was a good idea as it helped people to find out more about the various keys one can use in the Cargo.toml file, on the other hand it is annoying as it makes the file wide. I know, I can remove it.

And this is exactly what I deceided to do. Remove it from all the files in all the crates. Luckily, in this case, all the crates are located in the same folder:

perl -n -i -e 'print unless /^#/' */Cargo.toml

• Remember to use -i.bak if you don’t have the files in version control. Better yet, start using version control before you use this one-liner.
• -n tells perl to execute the command on every line.
• print unless /^#/ means: “Print the current line unless it starts with a # character.” (Both print and the // regex match apply to the (invisible) $_ variable that in this situation contains the current line.