AST inference not working

[lucian-poplin]

I am trying to parse the following string into an AST: !(type = "identify")

Lexing works correctly...

let str = `!(type = "identify")`
let res = lex(str)

...yet AST fails:

let resAst = ast(res["tokens"])

Error message is: LexerError: Unsupported or unrecognized token: [object Object]

The problem seems to be with the parentheses (no combination of them seems to be accepted) as well as with the prefix negation operator. Rewriting the input as type != "identify" allows correct inference of AST, yet this renders the package unusable.