Proposal: Split eval output

[acook]

If we split the printed output from the value output when the program is run it would allow the return value to be distinct from any online output and format them independently.

Issues

Colors from print bleed into results

Given:

println!("\x1b[31mHello World!"); 5 + 5

Then the output is all red until the next In: prompt.

Values cannot be formatted differently than the printed out

print!("foo")

Outputs:

out: foo()

But a better format might be:

foo
result: ()

This would bring IRust closer in line with other REPL formatting.

Solutions

Since we already need to capture the output to display it anyway, it should be simple enough to send the return value to a different location, such as a separate pipe, or after a simple delimiter.

Delimiter

Before the value is printed, include a simple delimiter. Even just --- and then split the text at the last one.

Pipe

Send the value to a pipe that the parent program watches.

[sigmaSd]

Hello, thanks your interest

Unfortunately, to do this we need to analyze the code provided by the user, which is not possible currently since we're just sticking the code in a binary and running it

A workaround is to write a plugin, that looks for print statements in the code , and put them last as you described, this won't work in all cases that's why it belongs into the plugins not in the main binary
https://github.com/sigmaSd/IRust/blob/master/SCRIPTS.md

[acook]

Hmm. I assumed it would be possible to not change the user's code at all, except for the final line, which I assume is already happening in order to print the output.

Something like this:

user code
user code
capture_variable = user code (final expression)
print ---
print capture-variable

But I took a look at the code and it is quite different from the other compiled-language REPLs I've played with, so I am probably missing something.

[sigmaSd]

If you have an example of a compiled language repl that does this I can take a look at it to see if there's something I can do here