[core] Console improvements #785
Conversation
|
|
||
| /** Represents a console for input and output operations. | ||
| */ | ||
| abstract class Console: | ||
| def unsafe: Console.Unsafe | ||
| final case class Console(unsafe: Console.Unsafe) extends AnyVal: |
There was a problem hiding this comment.
update the pattern like in the other effects
|
|
||
| /** Reads a line from the console. | ||
| * | ||
| * @return | ||
| * A String representing the line read from the console. | ||
| */ | ||
| def readln(using Frame): String < IO | ||
| def readln(using Frame): String < (IO & Abort[IOException]) = IO.Unsafe(Abort.get(unsafe.readln())) |
There was a problem hiding this comment.
Added tracking of IOException.
fwbrasil
force-pushed
the
console-improvements
branch
3 times, most recently
from
f8235b3 to
a46f774
Compare
fwbrasil
force-pushed
the
console-improvements
branch
from
a46f774 to
4548d95
Compare
| case Absent => Result.fail(new EOFException("Consoles.readln failed.")) | ||
| case Present(value) => Result.success(value) | ||
| } | ||
| def print(s: String)(using AllowUnsafe) = Result.catching(scala.Console.out.print(s)) |
There was a problem hiding this comment.
Will this catch only the type in the signature?
There was a problem hiding this comment.
Yes, the exception type is inferred but I've added explicit type params to avoid ambiguity
| Result.catching(Maybe(scala.Console.in.readLine())).flatMap { | ||
| case Absent => Result.fail(new EOFException("Consoles.readln failed.")) | ||
| case Present(value) => Result.success(value) |
There was a problem hiding this comment.
Maybe could have a method toSuccess[E](error: => E)?
There was a problem hiding this comment.
good idea! I've added maybe.toResult methods.
| val stdErr = new StringBuffer | ||
| val proxy = | ||
| new Proxy(console.unsafe): | ||
| override def print(s: String)(using AllowUnsafe) = Result.success(stdOut.append(s)).unit |
There was a problem hiding this comment.
Will this actually output?
There was a problem hiding this comment.
No, the idea is to only collect the output
| * @return | ||
| * A tuple containing the captured output (Out) and the computation result. | ||
| */ | ||
| def withOut[A, S](v: A < S)(using Frame): (Out, A) < (IO & S) = |
There was a problem hiding this comment.
I think I prefer the shorter version
There was a problem hiding this comment.
Since this PR is about Console and errors, I'd like to ask, whether Kyo is able to surface (instead of swallowing) the error(s) described in
- https://blog.sunfishcode.online/bugs-in-hello-world/
- https://github.com/sunfishcode/hello-world-vs-io-errors
?
No, we don't handle exit codes yet. Do you mind creating an issue for it? |
Happy to help: But the issue the blog post describes is even more about silently swallowing failures when writing to stream/pipe. So I thought it's relevant to this PR, which is changing things around Java's |
No description provided.