I\'ve come across the following code and can not understand what operation the double exclamation marks provide. This code-snipet is from a FAKE script used in a CICD system
The !!
operator takes a file pattern and returns a collection of files matching the pattern.
For example, if you want to print all text files in the current folder, you can write:
for file in !! "*.txt" do
printfn "%s" file
If you look at the operator definition in the source code, you can see that it is just an alias for creating a IGlobbingPattern
value (see the type definition) that includes files given by the specified pattern. The IGlobbingPattern
type implements IEnumerable
, so you can iterate over the files, but you can do a couple of other things with IGlobbingPattern
such as combining two file sets using ++
or removing some files from a file set using --
.