Golang target @ member variables are global

In the Java language target, variables declared in the @lexer::members section get declared within the lexer class. In the golang target the variables get declared as global variables. For example:

// TestLexer.g4
lexer grammar TestLexer;

@lexer::members {
var depth int
}

OPAR : '(' { depth++ } ;
CPAR : ')' { depth-- } ;

It is not clear if this is by design or not (but it would seem not). I am not familiar with the Antlr internals, but it seems the change is only related to the Go.stg template file. From this:

type struct {
*antlr.BaseLexer
channelNames []string
modeNames []string
// TODO: EOF string
}

To this (moving the template section for @lexer::members):

type struct {
*antlr.BaseLexer
channelNames []string
modeNames []string



// TODO: EOF string
}

And access the values via the receiver (aka l.depth).

My application was requiring recursive substitution - hence the ability to have lexer-instance specific values is important
(same issues apply to generated parsers).

Any pointers to operator error, or work-arounds highly appreciated.

Start with the Go.stg template and the TestLexer.g4 example. Generate the lexer and inspect how @lexer::members declarations are emitted and accessed; done means member variables are scoped to each generated lexer instance, with the same behavior applying to generated parsers.

Written by the indexing model from the issue text.