std_misc/process/pipe: remove unnecessary enclosing block

[ivan]

Fixes #702.

Thanks to mbrubeck and sfackler for helping me out with this.

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[mdinger]

This block (5 lines above this) should probably be removed because it is related to the braces you just removed. It makes little sense without them.

[ivan]

I left it in (and rephrased it slightly) because it seemed important to mention that the implicit dropping causes ChildStdin to close. (If someone has a let mut stdin = process.stdin;, the program will hang forever.)

Is the phrasing incorrect?

[mdinger]

Ah, I see. If it is important to emphasize that point, you should save it to a variable and include the braces which were just backed out to emphasize the dropping. IDK, I guess it might be nitpicky though. Not sure.

[ivan]

I don't object to putting the braces back and adding a let mut stdin = to emphasize the dropping, if that's the Rust way of doing things.

[mdinger]

Maybe the wording is just odd. Can't think of anything better right now.

[steveklabnik]

Any idea what w should do here?

[ivan]

To summarize, it could be

1. left as-is with a slightly confusing unnecessary block

2. changed as per my PR to remove the block, and rely on a non-obvious but commented implicit Drop

3. left as-is except with an extra let stdin = local inside the block, to emphasize the Drop

But I really don't know what to do here because I don't know how this is written in real Rust programs.

[steveklabnik]

I think I vote #1, after sleeping on it.

Thank you!

[ivan]

I think you voted for number 2 since you merged it?

[steveklabnik]

.... yes. I am very, very jetlagged, hehe. merging was what I wanted to do.