This commit is contained in:
🪞👃🪞 2025-07-19 08:42:08 +03:00
parent 291b917970
commit 238ac2e888
25 changed files with 1018 additions and 1147 deletions

View file

@ -5,6 +5,7 @@
extern crate const_panic;
use const_panic::{concat_panic, PanicFmt};
pub(crate) use ::tengri_core::*;
use std::ops::Deref;
pub(crate) use std::error::Error;
pub(crate) use std::fmt::Debug;
pub(crate) use std::sync::Arc;
@ -13,7 +14,80 @@ pub(crate) use konst::iter::{ConstIntoIter, IsIteratorKind};
pub(crate) use konst::string::{split_at, str_range, char_indices};
pub(crate) use thiserror::Error;
pub(crate) use self::DslError::*;
#[cfg(test)] mod test;
#[cfg(test)] mod dsl_test;
#[macro_export] macro_rules! dsl_read_advance (($exp:ident, $pat:pat => $val:expr)=>{{
let (head, tail) = $exp.advance(); $exp = tail; match head {
Some($pat) => $val, _ => Err(format!("(e4) unexpected {head:?}").into()) }}});
/// Coerce to [Val] for predefined [Self::Str] and [Self::Exp].
pub trait Dsl: Clone + Debug {
/// The string representation for a dizzle.
type Str: DslStr;
/// The string representation for a dizzle.
type Exp: DslExp;
/// Request the top-level DSL [Val]ue.
/// May perform cloning or parsing.
fn val (&self) -> Val<Self::Str, Self::Exp>;
fn err (&self) -> Option<DslError> {self.val().err()}
fn nil (&self) -> bool {self.val().nil()}
fn num (&self) -> Option<usize> {self.val().num()}
fn sym (&self) -> Option<Self::Str> {self.val().sym()}
fn key (&self) -> Option<Self::Str> {self.val().key()}
fn str (&self) -> Option<Self::Str> {self.val().str()}
fn exp (&self) -> Option<Self::Exp> {self.val().exp()}
fn exp_depth (&self) -> Option<isize> {self.val().exp_depth()}
fn exp_head (&self) -> Val<Self::Str, Self::Exp> {self.val().exp_head()}
fn exp_tail (&self) -> Self::Exp {self.val().exp_tail()}
fn exp_each (&self, f: impl Fn(&Self) -> Usually<()>) -> Usually<()> {
todo!()
}
fn advance (&self) -> (Val<Self::Str, Self::Exp>, Self::Exp) {
(self.exp_head(), self.exp_tail())
}
}
impl<'s> Dsl for &'s str {
type Str = &'s str;
type Exp = &'s str;
fn val (&self) -> Val<Self::Str, Self::Exp> { Val::Exp(0, self) }
}
impl<'s> Dsl for Cst<'s> {
type Str = &'s str;
type Exp = Cst<'s>;
fn val (&self) -> Val<Self::Str, Self::Exp> { Val::Exp(0, *self) }
}
impl Dsl for Ast {
type Str = Arc<str>;
type Exp = Ast;
fn val (&self) -> Val<Self::Str, Ast> { Val::Exp(0, self.clone()) }
}
impl<Str: DslStr, Exp: DslExp> Dsl for Token<Str, Exp> {
type Str = Str;
type Exp = Exp;
fn val (&self) -> Val<Str, Exp> { self.value.clone() }
}
impl<Str: DslStr, Exp: DslExp> Dsl for Val<Str, Exp> {
type Str = Str;
type Exp = Exp;
fn val (&self) -> Val<Str, Exp> { self.clone() }
}
/// The expression representation for a [Dsl] implementation.
/// [Cst] uses [CstIter]. [Ast] uses [VecDeque].
pub trait DslExp: PartialEq + Clone + Debug + Dsl {}
impl<T: PartialEq + Clone + Debug + Dsl> DslExp for T {}
/// The string representation for a [Dsl] implementation.
/// [Cst] uses `&'s str`. [Ast] uses `Arc<str>`.
pub trait DslStr: PartialEq + Clone + Default + Debug + AsRef<str> + Deref<Target = str> {
fn as_str (&self) -> &str { self.as_ref() }
fn as_arc (&self) -> Arc<str> { self.as_ref().into() }
}
impl<Str: PartialEq + Clone + Default + Debug + AsRef<str> + Deref<Target = str>> DslStr for Str {}
/// Enumeration of values that may figure in an expression.
/// Generic over string and expression storage.
#[derive(Clone, Debug, PartialEq, Default)]
@ -39,31 +113,20 @@ pub enum Val<Str, Exp> {
Error(DslError),
}
impl<Str: Copy, Exp: Copy> Copy for Val<Str, Exp> {}
impl<Str: DslStr, Exp: DslExp> Val<Str, Exp> {
pub fn convert <T: Dsl> (&self) -> Val<T::Str, T::Exp> where
T::Str: for<'a> From<&'a Str>,
T::Exp: for<'a> From<&'a Exp>
{
impl<S1, E1> Val<S1, E1> {
pub fn convert_to <S2, E2> (&self, to_str: impl Fn(&S1)->S2, to_exp: impl Fn(&E1)->E2) -> Val<S2, E2> {
match self {
Val::Nil => Val::Nil,
Val::Num(u) => Val::Num(*u),
Val::Sym(s) => Val::Sym(s.into()),
Val::Key(s) => Val::Key(s.into()),
Val::Str(s) => Val::Str(s.into()),
Val::Exp(d, x) => Val::Exp(*d, x.into()),
Val::Sym(s) => Val::Sym(to_str(s)),
Val::Key(s) => Val::Key(to_str(s)),
Val::Str(s) => Val::Str(to_str(s)),
Val::Exp(d, x) => Val::Exp(*d, to_exp(x)),
Val::Error(e) => Val::Error(*e)
}
}
}
/// The expression representation for a [Dsl] implementation.
/// [Cst] uses [CstIter]. [Ast] uses [VecDeque].
pub trait DslExp: PartialEq + Clone + Default + Debug + Dsl {}
impl<T: PartialEq + Clone + Default + Debug + Dsl> DslExp for T {}
/// The string representation for a [Dsl] implementation.
/// [Cst] uses `&'s str`. [Ast] uses `Arc<str>`.
pub trait DslStr: PartialEq + Clone + Default + Debug + AsRef<str> + std::ops::Deref<Target = str> {}
impl<T: PartialEq + Clone + Default + Debug + AsRef<str> + std::ops::Deref<Target = str>> DslStr for T {}
impl<Str: DslStr, Exp: DslExp + Dsl<Str=Str, Exp=Exp>> Val<Str, Exp> {
impl<Str: DslStr, Exp: DslExp + Dsl<Str=Str>> Val<Str, Exp> {
pub const fn err (&self) -> Option<DslError> {match self{Val::Error(e)=>Some(*e), _=>None}}
pub const fn nil (&self) -> bool {match self{Val::Nil=>true, _=>false}}
pub const fn num (&self) -> Option<usize> {match self{Val::Num(n)=>Some(*n), _=>None}}
@ -85,7 +148,9 @@ pub struct Token<Str, Exp> {
/// Length of span.
pub length: usize,
}
/// Tokens are copiable where possible.
impl<Str: Copy, Exp: Copy> Copy for Token<Str, Exp> {}
/// Token methods.
impl<Str, Exp> Token<Str, Exp> {
pub const fn end (&self) -> usize {
self.start.saturating_add(self.length) }
@ -99,83 +164,85 @@ impl<Str, Exp> Token<Str, Exp> {
Self { value: self.value, ..*self }
}
}
/// To the [Dsl], a token is equivalent to its `value` field.
impl<Str: DslStr, Exp: DslExp> Dsl for Token<Str, Exp> {
type Str = Str; type Exp = Exp;
fn dsl (&self) -> Val<Str, Exp> { self.value.clone() }
}
/// Coerce to [Val] for predefined [Self::Str] and [Self::Exp].
pub trait Dsl: Clone + Debug {
/// The string representation for a dizzle.
type Str: DslStr;
/// The expression representation for a dizzle.
type Exp: DslExp;
/// Request the top-level DSL [Val]ue.
/// May perform cloning or parsing.
fn dsl (&self) -> Val<Self::Str, Self::Exp>;
fn err (&self) -> Option<DslError> {self.dsl().err()}
fn nil (&self) -> bool {self.dsl().nil()}
fn num (&self) -> Option<usize> {self.dsl().num()}
fn sym (&self) -> Option<Self::Str> {self.dsl().sym()}
fn key (&self) -> Option<Self::Str> {self.dsl().key()}
fn str (&self) -> Option<Self::Str> {self.dsl().str()}
fn exp (&self) -> Option<Self::Exp> {self.dsl().exp()}
fn exp_depth (&self) -> Option<isize> {self.dsl().exp_depth()}
fn exp_head (&self) -> Val<Self::Str, Self::Exp> {self.dsl().exp_head()}
fn exp_tail (&self) -> Self::Exp {self.dsl().exp_tail()}
fn exp_each (&self, f: impl Fn(&Self) -> Usually<()>) -> Usually<()> { todo!() }
}
/// The most basic implementor of the [Dsl] trait.
impl<Str: DslStr, Exp: DslExp> Dsl for Val<Str, Exp> {
type Str = Str; type Exp = Exp;
fn dsl (&self) -> Val<Str, Exp> { self.clone() }
}
/// The abstract syntax tree (AST) can be produced from the CST
/// by cloning source slices into owned ([Arc]) string slices.
#[derive(Debug, Clone, Default, PartialEq)]
pub struct Ast(Arc<VecDeque<Arc<Token<Arc<str>, Ast>>>>);
pub type AstVal = Val<Arc<str>, Ast>;
pub type AstToken = Token<Arc<str>, Ast>;
impl Dsl for Ast {
type Str = Arc<str>; type Exp = Ast;
fn dsl (&self) -> Val<Arc<str>, Ast> { Val::Exp(0, Ast(self.0.clone())) }
}
impl<'s> From<&'s str> for Ast {
fn from (source: &'s str) -> Self {
let source: Arc<str> = source.into();
Self(CstIter(CstConstIter(source.as_ref()))
.map(|token|Arc::new(Token {
source: source.clone(),
start: token.start,
length: token.length,
value: match token.value {
Val::Nil => Val::Nil,
Val::Num(u) => Val::Num(u),
Val::Sym(s) => Val::Sym(s.into()),
Val::Key(s) => Val::Key(s.into()),
Val::Str(s) => Val::Str(s.into()),
Val::Exp(d, x) => Val::Exp(d, x.into()),
Val::Error(e) => Val::Error(e.into())
},
}))
.collect::<VecDeque<_>>()
.into())
}
}
impl<'s> From<Cst<'s>> for Ast {
fn from (cst: Cst<'s>) -> Self {
let mut tokens: VecDeque<_> = Default::default();
Self(tokens.into())
}
}
/// The concrete syntax tree (CST) implements zero-copy
/// parsing of the DSL from a string reference. CST items
/// preserve info about their location in the source.
/// CST stores strings as source references and expressions as [CstIter] instances.
#[derive(Debug, Copy, Clone, Default, PartialEq)]
pub struct Cst<'s>(pub CstIter<'s>);
pub type CstVal<'s> = Val<&'s str, Cst<'s>>;
pub type CstToken<'s> = Token<&'s str, Cst<'s>>;
#[derive(Debug, Copy, Clone, PartialEq, Default)]
pub enum Cst<'s> {
#[default] __,
Source(&'s str),
Token(CstToken<'s>),
Val(CstVal<'s>),
Iter(CstIter<'s>),
ConstIter(CstConstIter<'s>),
}
impl<'s> From<&'s str> for Cst<'s> {
fn from (src: &'s str) -> Self {
Cst::Source(src)
}
}
impl<'s> From<CstToken<'s>> for Cst<'s> {
fn from (token: CstToken<'s>) -> Self {
Cst::Token(token)
}
}
impl<'s> From<CstVal<'s>> for Cst<'s> {
fn from (val: CstVal<'s>) -> Self {
Cst::Val(val)
}
}
impl<'s> From<CstIter<'s>> for Cst<'s> {
fn from (iter: CstIter<'s>) -> Self {
Cst::Iter(iter)
}
}
impl<'s> From<CstConstIter<'s>> for Cst<'s> {
fn from (iter: CstConstIter<'s>) -> Self {
Cst::ConstIter(iter)
}
}
impl<'s> From<Cst<'s>> for Ast {
fn from (cst: Cst<'s>) -> Self {
match cst {
Cst::Source(source) | Cst::Iter(CstIter(CstConstIter(source))) |
Cst::ConstIter(CstConstIter(source)) =>
Ast::Source(source.into()),
Cst::Val(value) =>
Ast::Val(value.convert_to(|s|(*s).into(), |e|Box::new((*e).into()))),
Cst::Token(Token { source, start, length, value }) => {
let source = AsRef::<str>::as_ref(source).into();
let value = value.convert_to(|s|(*s).into(), |e|Box::new((*e).into()));
Ast::Token(Token { source, start, length, value })
},
_ => unreachable!()
}
}
}
/// The abstract syntax tree (AST) can be produced from the CST
/// by cloning source slices into owned ([Arc]) string slices.
#[derive(Debug, Clone, PartialEq, Default)]
pub enum Ast {
#[default] __,
Source(Arc<str>),
Token(Token<Arc<str>, Box<Ast>>),
Val(Val<Arc<str>, Box<Ast>>),
Exp(Arc<VecDeque<Arc<Token<Arc<str>, Ast>>>>),
}
impl<'s> From<&'s str> for Ast {
fn from (src: &'s str) -> Self {
Self::Source(src.into())
}
}
impl<'s, Str: DslStr, Exp: DslExp + Into<Ast> + 's> From<Token<Str, Exp>> for Ast {
fn from (Token { source, start, length, value }: Token<Str, Exp>) -> Self {
let source: Arc<str> = source.as_ref().into();
let value = value.convert_to(|s|s.as_ref().into(), |e|Box::new(e.clone().into()));
Self::Token(Token { source, start, length, value })
}
}
pub type CstVal<'s> = Val<&'s str, &'s str>;
pub type CstToken<'s> = Token<&'s str, &'s str>;
impl<'s> CstToken<'s> {
pub const fn slice (&self) -> &str {
str_range(self.source, self.start, self.end()) }
@ -188,19 +255,32 @@ impl<'s> CstToken<'s> {
self
}
pub const fn grow_exp (&'s mut self, depth: isize, source: &'s str) -> &mut Self {
self.value = Val::Exp(depth, Cst(CstIter(CstConstIter(source))));
self.value = Val::Exp(depth, source);
self
}
}
impl<'s> Dsl for Cst<'s> {
type Str = &'s str; type Exp = Cst<'s>;
fn dsl (&self) -> Val<Self::Str, Self::Exp> { Val::Exp(0, Cst(self.0)) }
}
impl<'s> From<&'s str> for Cst<'s> {
fn from (source: &'s str) -> Self {
Self(CstIter(CstConstIter(source)))
}
}
//impl<'s> From<&'s str> for Ast {
//fn from (source: &'s str) -> Ast {
//let source: Arc<str> = source.into();
//Ast(CstIter(CstConstIter(source.as_ref()))
//.map(|token|Arc::new(Token {
//source: source.clone(),
//start: token.start,
//length: token.length,
//value: match token.value {
//Val::Nil => Val::Nil,
//Val::Num(u) => Val::Num(u),
//Val::Sym(s) => Val::Sym(s.into()),
//Val::Key(s) => Val::Key(s.into()),
//Val::Str(s) => Val::Str(s.into()),
//Val::Exp(d, x) => Val::Exp(d, x.into()),
//Val::Error(e) => Val::Error(e.into())
//},
//}))
//.collect::<VecDeque<_>>()
//.into())
//}
//}
/// DSL-specific error codes.
#[derive(Error, Debug, Copy, Clone, PartialEq, PanicFmt)] pub enum DslError {
#[error("parse failed: not implemented")]
@ -283,20 +363,12 @@ pub const fn peek <'s> (mut value: CstVal<'s>, source: &'s str) -> CstToken<'s>
}
start = i;
length = 1;
if is_exp_start(c) {
value = Exp(1, Cst(CstIter(CstConstIter(str_range(source, i, i+1)))));
} else if is_str_start(c) {
value = Str(str_range(source, i, i+1));
} else if is_sym_start(c) {
value = Sym(str_range(source, i, i+1));
} else if is_key_start(c) {
value = Key(str_range(source, i, i+1));
} else if is_digit(c) {
value = match to_digit(c) { Ok(c) => Num(c), Err(e) => Error(e) };
} else {
value = Error(Unexpected(c));
break
}
value = if is_exp_start(c) { Exp(1, str_range(source, i, i+1)) }
else if is_str_start(c) { Str(str_range(source, i, i+1)) }
else if is_sym_start(c) { Sym(str_range(source, i, i+1)) }
else if is_key_start(c) { Key(str_range(source, i, i+1)) }
else if is_digit(c) { match to_digit(c) { Ok(c) => Num(c), Err(e) => Error(e) } }
else { value = Error(Unexpected(c)); break }
} else if matches!(value, Str(_)) {
if is_str_end(c) {
break
@ -323,13 +395,13 @@ pub const fn peek <'s> (mut value: CstVal<'s>, source: &'s str) -> CstToken<'s>
}
} else if let Exp(depth, exp) = value {
if depth == 0 {
value = Exp(0, Cst(CstIter(CstConstIter(str_range(source, start, start + length)))));
value = Exp(0, str_range(source, start, start + length));
break
}
length += 1;
value = Exp(
if c == ')' { depth-1 } else if c == '(' { depth+1 } else { depth },
Cst(CstIter(CstConstIter(str_range(source, start, start + length))))
str_range(source, start, start + length)
);
} else if let Num(m) = value {
if is_num_end(c) {
@ -378,22 +450,6 @@ pub const fn to_digit (c: char) -> Result<usize, DslError> {
_ => return Err(Unexpected(c))
})
}
/// `State` + [Dsl] -> `Self`.
pub trait FromDsl<State>: Sized {
fn try_from_dsl (state: &State, dsl: &impl Dsl) -> Perhaps<Self>;
fn from_dsl (state: &State, dsl: &impl Dsl, err: impl Fn()->Box<dyn Error>) -> Usually<Self> {
match Self::try_from_dsl(state, dsl)? { Some(dsl) => Ok(dsl), _ => Err(err()) } }
}
/// `self` + `Options` -> [Dsl]
pub trait IntoDsl { /*TODO*/ }
/// `self` + [Dsl] -> `Item`
pub trait DslInto<Item> {
fn try_dsl_into (&self, dsl: &impl Dsl) -> Perhaps<Item>;
fn dsl_into (&self, dsl: &impl Dsl, err: impl Fn()->Box<dyn Error>) -> Usually<Item> {
match Self::try_dsl_into(self, dsl)? { Some(dsl) => Ok(dsl), _ => Err(err()) } }
}
/// `self` + `Item` -> [Dsl]
pub trait DslFrom { /*TODO*/ }
/// Implement type conversions.
macro_rules! from(($($Struct:ty { $(
@ -421,3 +477,53 @@ macro_rules! from(($($Struct:ty { $(
//<'s> (iter: CstIter<'s>) Ast(iter.map(|x|x.value.into()).collect::<VecDeque<_>>().into());
//<D: Dsl> (token: Token<D>) Ast(VecDeque::from([dsl_val(token.val())]).into()); }
//}
/// `T` + [Dsl] -> `Self`.
pub trait FromDsl<T>: Sized {
fn from_dsl (state: &T, dsl: &impl Dsl) -> Perhaps<Self>;
fn from_dsl_or (state: &T, dsl: &impl Dsl, err: Box<dyn Error>) -> Usually<Self> {
Self::from_dsl(state, dsl)?.ok_or(err)
}
fn from_dsl_or_else (state: &T, dsl: &impl Dsl, err: impl Fn()->Box<dyn Error>) -> Usually<Self> {
Self::from_dsl(state, dsl)?.ok_or_else(err)
}
}
impl<T: FromDsl<U>, U> DslInto<T> for U {
fn dsl_into (&self, dsl: &impl Dsl) -> Perhaps<T> {
T::from_dsl(self, dsl)
}
}
/// `self` + [Dsl] -> `T`
pub trait DslInto<T> {
fn dsl_into (&self, dsl: &impl Dsl) -> Perhaps<T>;
fn dsl_into_or (&self, dsl: &impl Dsl, err: Box<dyn Error>) -> Usually<T> {
self.dsl_into(dsl)?.ok_or(err)
}
fn dsl_into_or_else (&self, dsl: &impl Dsl, err: impl Fn()->Box<dyn Error>) -> Usually<T> {
self.dsl_into(dsl)?.ok_or_else(err)
}
}
/// `self` + `T` + -> [Dsl]
pub trait IntoDsl<T> {
fn into_dsl (&self, state: &T) -> Perhaps<impl Dsl>;
fn into_dsl_or (&self, state: &T, err: Box<dyn Error>) -> Usually<impl Dsl> {
self.into_dsl(state)?.ok_or(err)
}
fn into_dsl_or_else (&self, state: &T, err: impl Fn()->Box<dyn Error>) -> Usually<impl Dsl> {
self.into_dsl(state)?.ok_or_else(err)
}
}
/// `self` + `T` -> [Dsl]
pub trait DslFrom<T> {
fn dsl_from (&self, dsl: &impl Dsl) -> Perhaps<impl Dsl>;
fn dsl_from_or (&self, dsl: &impl Dsl, err: Box<dyn Error>) -> Usually<impl Dsl> {
self.dsl_from(dsl)?.ok_or(err)
}
fn dsl_from_or_else (&self, dsl: &impl Dsl, err: impl Fn()->Box<dyn Error>) -> Usually<impl Dsl> {
self.dsl_from(dsl)?.ok_or_else(err)
}
}

0
dsl/src/dsl_test.rs Normal file
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@ -1,104 +0,0 @@
use crate::*;
use proptest::prelude::*;
#[test] fn test_iters () {
let mut iter = crate::CstIter::new(&":foo :bar");
let _ = iter.next();
}
#[test] const fn test_const_iters () {
let iter = crate::CstConstIter::new(&":foo :bar");
let _ = iter.next();
}
#[test] fn test_num () {
let _digit = Token::to_digit('0');
let _digit = Token::to_digit('x');
let _number = Token::to_number(&"123");
let _number = Token::to_number(&"12asdf3");
}
//proptest! {
//#[test] fn proptest_source_iter (
//source in "\\PC*"
//) {
//let mut iter = crate::CstIter::new(&source);
////let _ = iter.next()
//}
//#[test] fn proptest_token_iter (
//source in "\\PC*"
//) {
//let mut iter = crate::TokenIter::new(&source);
////let _ = iter.next();
//}
//}
//#[cfg(test)] mod test_token_prop {
//use crate::{Cst, CstMeta, Value::*};
//use proptest::prelude::*;
//proptest! {
//#[test] fn test_token_prop (
//source in "\\PC*",
//start in usize::MIN..usize::MAX,
//length in usize::MIN..usize::MAX,
//) {
//let token = Cst(Nil, CstMeta { source: &source, start, length });
//let _ = token.slice();
//}
//}
//}
#[test] fn test_token () -> Result<(), Box<dyn std::error::Error>> {
use crate::Val::*;
let source = ":f00";
let mut token = CstToken::new(source, 0, 1, Sym(":"));
token = token.grow_sym();
assert_eq!(token, CstToken::new(source, 0, 2, Sym(":f")));
token = token.grow_sym();
assert_eq!(token, CstToken::new(source, 0, 3, Sym(":f0")));
token = token.grow_sym();
assert_eq!(token, CstToken::new(source, 0, 4, Sym(":f00")));
assert_eq!(None, CstIter::new("").next());
assert_eq!(None, CstIter::new(" \n \r \t ").next());
assert_eq!(Err(Unexpected('a')), CstIter::new(" 9a ").next().unwrap().value());
assert_eq!(Num(7), CstIter::new("7").next().unwrap().value());
assert_eq!(Num(100), CstIter::new(" 100 ").next().unwrap().value());
assert_eq!(Sym(":123foo"), CstIter::new(" :123foo ").next().unwrap().value());
assert_eq!(Sym("@bar456"), CstIter::new(" \r\r\n\n@bar456\t\t\t").next().unwrap().value());
assert_eq!(Key("foo123"), CstIter::new("foo123").next().unwrap().value());
assert_eq!(Key("foo/bar"), CstIter::new("foo/bar").next().unwrap().value());
//assert_eq!(Str("foo/bar"), CstIter::new("\"foo/bar\"").next().unwrap().value());
//assert_eq!(Str("foo/bar"), CstIter::new(" \"foo/bar\" ").next().unwrap().value());
Ok(())
}
//#[cfg(test)] #[test] fn test_examples () -> Result<(), DslErr> {
//// Let's pretend to render some view.
//let source = include_str!("../../tek/src/view_arranger.edn");
//// The token iterator allows you to get the tokens represented by the source text.
//let mut view = TokenIter(source);
//// The token iterator wraps a const token+source iterator.
//assert_eq!(view.0.0, source);
//let mut expr = view.peek();
//assert_eq!(view.0.0, source);
//assert_eq!(expr, Some(Token {
//source, start: 0, length: source.len() - 1, value: Exp(0, CstIter::new(&source[1..]))
//}));
////panic!("{view:?}");
////panic!("{:#?}", expr);
////for example in [
////include_str!("../../tui/examples/edn01.edn"),
////include_str!("../../tui/examples/edn02.edn"),
////] {
//////let items = Dsl::read_all(example)?;
//////panic!("{layout:?}");
//////let content = <dyn ViewContext<::tengri_engine::tui::Tui>>::from(&layout);
////}
//Ok(())
//}