Imported From: https://issues.scala-lang.org/browse/SI-8918?orig=1
Reporter: Guillaume Massé (masgui)

@som-snytt said:
You cannot escape!

Guillaume Massé (masgui) said:
why not ?

Finally, an identifier may also be formed by an arbitrary string between back-quotes (host systems may impose some restrictions on which strings are legal for identifiers). The identifier then is composed of all characters excluding the backquotes themselves.

• http://www.scala-lang.org/files/archive/spec/2.11/01-lexical-syntax.html#identifiers

@som-snytt said:
I meant it in the sense of, "Mwa-ha-ha!" evil cackling.

But also, an id is an id. Backquotes don't change anything here. Reduced:

scala> val - = 2
-: Int = 2

scala> $minus
res0: Int = 2

scala> -  // newline or semi should disambiguate unary op
     | 1
<console>:2: error: illegal start of simple expression
       1
^

scala> -(      // contrast
     | 1
     | )
res3: Int = -1

@som-snytt said (edited on Oct 25, 2015 7:42:45 AM UTC):
scala/scala#4059

scala/scala#4301

where they must be followed by a simple expr to be taken as unary ops.