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use crate::expected_token_err;
use crate::lexer::token::TokenKind;
use crate::parser::ast::variables::BracedVariableVariable;
use crate::parser::ast::variables::SimpleVariable;
use crate::parser::ast::variables::Variable;
use crate::parser::ast::variables::VariableVariable;
use crate::parser::error::ParseResult;
use crate::parser::expressions;
use crate::parser::internal::utils;
use crate::parser::state::State;
pub fn simple_variable(state: &mut State) -> ParseResult<SimpleVariable> {
if let TokenKind::Variable(name) = state.stream.current().kind.clone() {
let span = state.stream.current().span;
state.stream.next();
return Ok(SimpleVariable { span, name });
}
expected_token_err!("a variable", state)
}
pub fn dynamic_variable(state: &mut State) -> ParseResult<Variable> {
match state.stream.current().kind.clone() {
TokenKind::Variable(name) => {
let span = state.stream.current().span;
state.stream.next();
Ok(Variable::SimpleVariable(SimpleVariable { span, name }))
}
TokenKind::DollarLeftBrace => {
let start = state.stream.current().span;
state.stream.next();
let expr = expressions::lowest_precedence(state)?;
let end = utils::skip_right_brace(state)?;
Ok(Variable::BracedVariableVariable(BracedVariableVariable {
start,
variable: Box::new(expr),
end,
}))
}
TokenKind::Dollar if state.stream.peek().kind == TokenKind::LeftBrace => {
let start = state.stream.current().span;
state.stream.next();
state.stream.next();
let expr = expressions::lowest_precedence(state)?;
let end = utils::skip_right_brace(state)?;
Ok(Variable::BracedVariableVariable(BracedVariableVariable {
start,
variable: Box::new(expr),
end,
}))
}
TokenKind::Dollar => {
let span = state.stream.current().span;
state.stream.next();
let variable = dynamic_variable(state)?;
Ok(Variable::VariableVariable(VariableVariable {
span,
variable: Box::new(variable),
}))
}
_ => {
expected_token_err!("a variable", state)
}
}
}