Please do not forget this use case:
"""
one
"two"
three
"""
I really like this about """ now. Same example with escaping single quotes:
"
one
\"two\"
three
"
4 Likes
``` would allow preserving the current semantics of """ and ", and avoid the need to quote embedded single quotes:
```
one
"two"
three
```
There are other alternatives for creating a fenced block that could be worth exploring, like the heredoc:
val multiLineString = <<<EOF
one
"two"
three
EOF
println(<<<EOF
one
"two"
three
EOF
)
Yes, but the problem is that we cannot change the semantics of """ and we will not introduce a third quote such as ```. So that leaves us with multiline " which is still available. But having to escape quotes at start of lines is not nice, I agree.
One solution to this would be to use the existing stripMargin. I.e. you could write the example like this:
"
|one
|"two"
|three
".stripMargin
That’s just the old stripMargin we have, used in the new context.
heredoc idea looks interesting and could be changed a bit to reuse " syntax, i.e.
val x = "EOF
one
"two"
"""three"""
EOF
1 Like
A conservative approach would be to have a new stripping interpolator that:
val x = str”foo
|bar
|baz”
And deprecate the old one.
Using a custom interpolator is not good enough as I mentioned before: Multiline string literals: can we get rid of the need for stripMargin?
Hear, hear! or rather Here, here! for heredoc.
REPL lets you specify a margin character, by analogy to detabbing <<- or <<~ style.
scala> :paste <| EOF
// Entering paste mode (EOF to finish)
|class C { def f = 42 }
EOF
// Exiting paste mode, now interpreting.
defined class C
Probably there would be more demand for this sort of thing, and uniformity across snippets, scripts, and so-called normal code, if Scala were used more in anger for “scaled” development. Right now, as per the other thread, my main snippet doesn’t scale from REPL to @main.
As for Scaladoc, we’d need to standardize the spelling of hereDoc. I’d be inclined to pronounce it like “heretic”, as it is a syntactic tic.
It’s clear heredoc syntax isn’t used in REPL because no one complains about it. I’d expect the first case to detect the desired indent.
scala> :pa <-
// Entering paste mode (ctrl-D to finish)
val s = """
hi
world
"""
// Exiting paste mode, now interpreting.
s: String =
"
hi
world
"
scala> :pa <*
// Entering paste mode (ctrl-D to finish)
val s = """
* hi
* world
"""
// Exiting paste mode, now interpreting.
s: String =
"
hi
world
"
scala>
It’s encouraging that REPL already prints multiline singly-quoted strings.
The current limitation on interpolators excludes val s = <<EOF"my text... in some shoehorning of syntax. Reminder that the result can also take parameters, such as
val s = sm" * strip comment asterisk"("* ")
I haven’t read through all the comments, just wanted to mention that groovy has a stripIndent function. I did not have a look at their algorithm but maybe it is good enough (never had problems at least):
I see that you linked to a post that said it wasn’t optimal because you felt the default could do it, but I don’t see that it “is not good enough”. It is a fact of life to deal with deprecations. Adding a new interpolator and deprecating the old one seems “good enough” to me. Adding more syntax is a real cost.
The problem is that we want this behavior for all interpolators, not just one specific interpolator.