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use crate::expression::{Expression, Ident};
#[derive(Clone)]
pub enum Statement {
Expression(Box<Expression>),
Print(Box<Expression>),
Declare {
ident: Ident,
local: bool,
expr: Box<Expression>,
},
// Var(Token, Expression),
Block(Vec<Statement>),
If {
cond: Box<Expression>,
then: Vec<Statement>,
else_cond: Option<Vec<Statement>>,
},
While {
cond: Box<Expression>,
block: Vec<Statement>,
},
NumericFor {
/** no need to track variable depth */
ident: usize,
start: Box<Expression>,
end: Box<Expression>,
step: Option<Box<Expression>>,
block: Vec<Statement>,
},
Return(Box<Expression>),
// Break,
// Continue,
// Function {
// ident: usize,
// local: bool,
// args: Vec<usize>,
// block: Vec<Statement>,
// },
// Function(Token, Vec<Token>, Box<Statement>),
// Return(Token, Option<Expression>),
// Class(Token, Option<Expression>, Vec<Statement>),
// Import(Token, Option<Token>),
// EOF,
Skip,
InvalidStatement,
}
impl std::fmt::Display for Statement {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
match self {
Statement::Expression(expr) => write!(f, "$${}", expr),
Statement::Skip => write!(f, ";"),
Statement::Print(expr) => write!(f, "$print$ {}", expr),
Self::Return(expr) => write!(f, "$return$ {}", expr),
Statement::Declare {
ident,
local,
expr: value,
} => write!(
f,
"$declare$ {} {}:{} := {}",
if *local { "local" } else { "global" },
ident.0,
ident.1,
value
),
Statement::InvalidStatement => write!(f, "!invalid!"),
Statement::Block(statements) => {
let mut s = String::new();
for statement in statements {
s.push_str(&format!("\n||{}", statement));
}
write!(f, "$block$ {}", s)
}
Statement::If {
cond,
then,
else_cond,
} => {
let mut s = String::new();
for statement in then {
s.push_str(&format!("\n||{}", statement));
}
let mut s = format!("$if$ {} then {}", cond, s);
if let Some(else_cond) = else_cond {
let mut s2 = String::new();
for statement in then {
s2.push_str(&format!("\n||{}", statement));
}
s.push_str(&format!(" else {}", s2));
}
write!(f, "{}", s)
}
Statement::While { cond, block } => {
let mut s = String::new();
for statement in block {
s.push_str(&format!("\n||{}", statement));
}
write!(f, "$while$ {} {}", cond, s)
}
Statement::NumericFor {
ident,
start,
end,
step,
block,
} => {
let mut s = String::new();
for statement in block {
s.push_str(&format!("\n||{}", statement));
}
write!(
f,
"$for$ {} := {} to {} step {}",
ident,
start,
end,
match step {
Some(step) => format!("{}", step),
None => format!("1"),
}
)
} // Statement::Function {
// ident,
// local,
// args,
// block,
// } => {
// let mut s = String::new();
// for statement in block {
// s.push_str(&format!("\n||{}", statement));
// }
// write!(
// f,
// "$function$ {} {} {}",
// if *local { "local" } else { "global" },
// ident,
// s
// )
// }
}
}
}