Multiline string rejects line terminator elision

[infogulch]

What version of CUE are you using (cue version)?

$ cue version
cue version v0.10.0

go version go1.23.0
      -buildmode exe
       -compiler gc
       -trimpath true
     CGO_ENABLED 0
          GOARCH amd64
            GOOS linux
         GOAMD64 v1
cue.lang.version v0.10.0

Does this issue reproduce with the latest stable release?

Yes

What did you do?

Tried to evaluate the string from the spec under String and byte sequence literals:

"""
    lily:
    out of the water
    out of itself

    bass
    picking \
    bugs
    off the moon
        — Nick Virgilio, Selected Haiku, 1988
    """

What did you expect to see?

According to the spec page it should be equivalent to:

"lily:\nout of the water\nout of itself\n\n" +
"bass\npicking bugs\noff the moon\n" +
"    — Nick Virgilio, Selected Haiku, 1988"

What did you see instead?

cannot get syntax for "-": unknown escape sequence:
    -:7:14

Notes

Here's a playground with this issue: https://cuelang.org/play/?id=7uimnxuUVGR#w=function&i=cue&f=eval&o=cue

A smaller reproduction case: https://cuelang.org/play/?id=hxhDZo_g4zz#w=function&i=cue&f=eval&o=cue

[infogulch]

Ah this seems related to https://github.com/cue-lang/cue/issues/2317

[mvdan]

Yes; this is #2317. Line continuations with backslashes are not implemented right now.