Parse Error related to antlr4.6 update in .2809 prerelease build

[Stevefb]

Using the prerelease build .2809, this code generates a parse error:

Public Sub Foo()
    Dim a As Integer
    Dim b As Integer
    Dim c As Integer
    a = 1
    b = 2
    c = a - b  ' <<<<<<<< Parse Error, No alternative input 
    Debug.Print c
End Sub

[Stevefb]

Just confirmed the issue is NOT in Rubberduck v2.1.2.2803-pre

[ThunderFrame]

looks like it might be related to B_CHAR. Do you get the same parse error when the b variable is named something other than b?

[MDoerner]

It cannot be B_Char since that does not exist anymore.

[Vogel612]

it's probably LETTER_RANGE. Could you check whether the problem persists if you rename a to something with more than a single letter?

[Stevefb]

Thanks guys, confirmed that changing variable name from 'a' to something else works-around the parse error.

Public Sub Foo()
    Dim aye As Integer
    Dim b As Integer
    Dim c As Integer
    aye = 1
    b = 2
    c = aye - b
    Debug.Print c
End Sub

[quentinharris]

Appears to be that single letter followed by a '-' will raise the error. So single letter variables then space then "-" cause this. Lengthening the string e.g. 'ab' rather than 'a' avoids this. I tried different single letters and operators. Interestingly you can have a - -b but not a - b. As @MDoerner has mentioned in chat, this is more precisely raised by singleLetter hyphen singleLetter.