proposal: embed: //go:embed directive to embed current file if no argument given

[sding3]

For a variable located in foo.go to embed the file foo.go, we need:

//go:embed foo.go
var file string

It would be convenient if the embed directive interprets the empty argument as to embed the current source file, e.g.:

//go:embed
var file string

I was looking to do documentation generation by parsing out godoc comment of a go source file that contains many configuration parameters for a program by embedding that file and parsing the AST. By allowing the embed directive embed the source file that the directive appears in when no arguments are given, I no longer have to couple the embed directive argument with that source file's filename (i.e., no longer need to update the embed directive every time the source code's filename is changed).

[ianlancetaylor]

This seems very special purpose, and rather confusing when reading the code.

[rittneje]

I don't really understand what you are trying to do, but have you considered using go generate instead? Then you will have access to the GOFILE env var that it sets.

[sding3]

This seems very special purpose, and rather confusing when reading the code.

This is not a big deal, as the file being renamed without the embed directive being updated will lead to a test failure. But currently the embed directive without argument is an error, so I figured that we might as well make the default do something useful. I suppose the current error is helpful in preventing someone accidentally including a file in the compiled binary that they didn't intend.