[SR-8793] Access to file data and functions in REPL

[swift-ci]

Previous ID	SR-8793
Radar	rdar://problem/42831983
Original Reporter	jkleiser (JIRA User)
Type	New Feature

Additional Detail from JIRA

Votes	0
Component/s	Compiler, LLDB for Swift
Labels	New Feature, REPL
Assignee	None
Priority	Medium

md5: b158931f122cf4b19148d1be6afab6e4

Issue Description:

It would be great if it was possible to run the `swift` binary with an option, e.g. `-i` for "interactive", that would give access in the REPL to (public) data and functions from the file that was just executed. Today, when doing `swift myscript.swift` from the command line, one is returned to the shell as soon as the script file has been executed. What I ask for, is a way to remain in the REPL and to be able to experiment further with the data and functions that the script provided.

[belkadan]

Tagging as LLDB since I think we'd implement this by having the existing REPL run a script rather than by having the existing JIT drop you into the REPL. cc jingham@apple.com (JIRA User)

[swift-ci]

Comment by Jim Ingham (JIRA)

We also had a request for individual commands, something like:

> swift -i -c "import Foundation"
 

Both approaches would be useful, and neither would be hard to implement in lldb.

[belkadan]

We may want that to also match the syntax for SR-5860, even if the implementation is different.