Custom sed Separators

When using sed for a substitution I was under the impression that / had to be used as a separator for the segments.

sed 's/pattern/replacement/options'

Turns out you can use whatever separator you want. This is incredibly handy if the pattern you are substituting contains slashes - such as urls. By selecting a different separator all of the escaping can be avoided.

Without custom separator - lots of escaping

sed 's/\/posts\/specifying-sed-separators/\/posts\/custom-sed-separators/'

With custom separator - more clear

sed 's|/posts/specifying-sed-separators|/posts/custom-sed-separators|'

Sed is really good at figuring out what separator you are using and working with it. It’s worth calling out the community tends to use # as a separator when a custom one is needed. If you use more exotic separators like I did above it could cause confusion.

sed 's#/posts/specifying-sed-separators#/posts/custom-sed-separators#'