Manual claims that run returns nothing

[adomasbaliuka]

This manual page claims that run returns nothing. However (in version v1.5.3) it returns a Process object (I'm not sure if it always does).

Note: this commit does not (yet) propose changes that can be merged because I don't know for sure how to correct the error.
Note: the more recent (unreleased) versions of this file seem to have the same error.

To reproduce:

julia> VERSION
v"1.5.3"
julia> typeof(run(`echo`))
Base.Process

[jmkuhn]

You could clarify the meaning by changing the order of the sentence:

If the external command fails to run successfully, the run method returns nothing, and throws an ErrorException.

Edit: the specific exception that is thrown depends on the reason for the failure.

[adomasbaliuka]

@jmkuhn Thanks to your comment, I now possibly understand the intended meaning of the sentence. However, I still disagree with the wording: a function that throws an exception cannot return any object. In particular, it does not return nothing, which is an object of type Nothing. If my understanding of this matter is correct, I believe it would be better to completely remove the statement about returning something in case of error.

Suggested change:
If the external command fails to run successfully, the run method throws an ErrorException.

[adomasbaliuka]

@jmkuhn I updated the pull request. The proposed state of the manual file contains changes that I would agree with.

Note: I have not proposed (and don't know the procedure for proposing) adoption of this change for the same manual file in different versions of Julia.

Reproduction of latest commit message (in case it is overlooked):

The original text could be misinterpreted as saying that run returns nothing, which is an object of type Nothing. As far as I can tell, there is no circumstance where the method run(cmds::Base.AbstractCmd, args...; wait) in Base at process.jl:437 (line as of v1.5.3) actually returns nothing::Nothing.

I deleted the remark about returning nothing from the manual page in question.

[JeffBezanson]

Welcome, thanks for finding this!