Function parse_ltl_expr 

pub(crate) fn parse_ltl_expr<T>(
    pair: Pair<'_, Rule>,
    builder: &T,
    ctx: &TLAParsingContext<'_>,
) -> Result<ELTLExpression, Box<Error<()>>>
where
    T: IsDeclared<Variable> + IsDeclared<Location> + IsDeclared<Parameter>,

Parse an ltl expression into a single ltl expression

This function parses an ltl expression with operator precedence and returns the corresponding ltl expression. The function returns an error if the expression refers to an unknown location