remove DslKey

dsl/README.md

@@ -95,7 +95,7 @@ or configuration statements, and look like this:
 
 ## implementation notes
 
-### `DslExp` trait behavior
+### `DslExpr` trait behavior
 
 this is the trait which differentiates "a thing" from
 "a thing that is many things".

dsl/src/dsl.rs

@@ -18,7 +18,6 @@ pub(crate) use self::DslError::*;
 mod dsl_conv; pub use self::dsl_conv::*;
 mod dsl_ns;   pub use self::dsl_ns::*;
 mod dsl_src;  pub use self::dsl_src::*;
-mod dsl_type; pub use self::dsl_type::*;
 #[cfg(test)] mod dsl_test;
 /// DSL-specific result type.
 pub type DslResult<T> = Result<T, DslError>;
@@ -40,3 +39,246 @@ pub enum DslError {
     #[error("end reached")]
     End
 }
+fn ok_flat <T> (x: Option<DslPerhaps<T>>) -> DslPerhaps<T> {
+    Ok(x.transpose()?.flatten())
+}
+pub const fn is_space (c: char) -> bool {
+    matches!(c, ' '|'\n'|'\r'|'\t')
+}
+pub const fn no_trailing_non_space (
+    src: &str, offset: usize, context: Option<&'static str>
+) -> DslResult<()> {
+    Ok(for_each!((i, c) in char_indices(str_range(src, offset, src.len())) => if !is_space(c) {
+        return Err(Unexpected(c, Some(offset + i), if let Some(context) = context {
+            Some(context)
+        } else {
+            Some("trailing non-space")
+        }))
+    }))
+}
+pub const fn peek (src: &str) -> DslPerhaps<&str> {
+    Ok(Some(if let Ok(Some(expr)) = expr_peek(src) { expr } else
+            if let Ok(Some(word)) = word_peek(src) { word } else
+            if let Ok(Some(num))  = num_peek(src)  { num  } else
+            if let Ok(Some(text)) = text_peek(src) { text } else
+            if let Err(e) = no_trailing_non_space(src, 0, Some("peek")) { return Err(e) }
+            else { return Ok(None) }))
+}
+pub const fn seek (src: &str) -> DslPerhaps<(usize, usize)> {
+    Ok(Some(if let Ok(Some(expr)) = expr_seek(src) { expr } else
+            if let Ok(Some(word)) = word_seek(src) { word } else
+            if let Ok(Some(num))  = num_seek(src)  { num  } else
+            if let Ok(Some(text)) = text_seek(src) { text } else
+            if let Err(e) = no_trailing_non_space(src, 0, Some("seek")) { return Err(e) }
+            else { return Ok(None) }))
+}
+pub const fn peek_tail (src: &str) -> DslPerhaps<&str> {
+    match seek(src) {
+        Err(e) => Err(e),
+        Ok(None) => Ok(None),
+        Ok(Some((start, length))) => {
+            let tail = str_range(src, start + length, src.len());
+            for_each!((_i, c) in char_indices(tail) => if !is_space(c) { return Ok(Some(tail)) });
+            Ok(None)
+        },
+    }
+}
+
+#[macro_export] macro_rules! dsl_type (($T:ident { $($trait:tt)* } {
+    pub const fn $peek:ident      $($_1:tt)?;
+    pub const fn $peek_only:ident $($_2:tt)?;
+    pub const fn $seek:ident      $($_3:tt)?;
+    pub const fn $seek_start:ident  ($source1:ident) $body1:block
+    pub const fn $seek_length:ident ($source2:ident) $body2:block
+})=>{
+    pub trait $T: Dsl { $($trait)* }
+    impl<D: Dsl> $T for D {}
+    /// Find a slice corrensponding to a syntax token.
+    pub const fn $peek (source: &str) -> DslPerhaps<&str> {
+        match $seek(source) {
+            Err(e) => Err(e),
+            Ok(None) => Ok(None),
+            Ok(Some((start, length))) => Ok(Some(str_range(source, start, start + length))),
+        }
+    }
+    /// Find a slice corrensponding to a syntax token
+    /// but return an error if it isn't the only thing
+    /// in the source.
+    pub const fn $peek_only (source: &str) -> DslPerhaps<&str> {
+        match $seek(source) {
+            Err(e) => Err(e),
+            Ok(None) => Ok(None),
+            Ok(Some((start, length))) => {
+                if let Err(e) = no_trailing_non_space(source, start + length, Some("peek_only")) { return Err(e) }
+                Ok(Some(str_range(source, start, start + length)))
+            }
+        }
+    }
+    /// Find a start and length corresponding to a syntax token.
+    pub const fn $seek (source: &str) -> DslPerhaps<(usize, usize)> {
+        match $seek_start(source) {
+            Err(e) => Err(e),
+            Ok(None) => Ok(None),
+            Ok(Some(start)) => match $seek_length(str_from(source, start)) {
+                Ok(Some(length)) => Ok(Some((start, length))),
+                Ok(None) => Ok(None),
+                Err(e) => Err(e),
+            },
+        }
+    }
+    pub const fn $seek_start  ($source1: &str) -> DslPerhaps<usize> $body1
+    pub const fn $seek_length ($source2: &str) -> DslPerhaps<usize> $body2
+});
+
+pub const fn is_expr_start (c: char) -> bool { c == '(' }
+pub const fn is_expr_end (c: char) -> bool { c == ')' }
+dsl_type!(DslExpr {
+    fn expr  (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(expr_peek_inner_only))}
+    fn head (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(peek))}
+    fn tail (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(peek_tail))}
+    /// my other car is a cdr :<
+    fn each (&self, mut cb: impl FnMut(&str)->Usually<()>) -> Usually<()> {
+        Ok(if let Some(head) = self.head()? {
+            cb(head)?;
+            if let Some(tail) = self.tail()? {
+                tail.each(cb)?;
+            }
+        })
+    }
+} {
+    pub const fn expr_peek      [generated];
+    pub const fn expr_peek_only [generated];
+    pub const fn expr_seek      [generated];
+    pub const fn expr_seek_start (src) {
+        for_each!((i, c) in char_indices(src) =>
+            if is_expr_start(c) { return Ok(Some(i)) } else
+            if !is_space(c) { return Err(Unexpected(c, Some(i), Some("expected expression start"))) });
+        Ok(None)
+    }
+    pub const fn expr_seek_length (src) {
+        let mut depth = 0;
+        for_each!((i, c) in char_indices(src) =>
+            if is_expr_start(c) { depth += 1; } else
+            if is_expr_end(c) {
+                if depth == 0 {
+                    return Err(Unexpected(c, Some(i), Some("expected expression end")))
+                } else if depth == 1 {
+                    return Ok(Some(i + 1))
+                } else {
+                    depth -= 1;
+                }
+            });
+        Err(Incomplete)
+    }
+});
+
+pub const fn expr_peek_inner (src: &str) -> DslPerhaps<&str> {
+    match expr_peek(src) {
+        Ok(Some(peeked)) => {
+            let len = peeked.len();
+            let start = if len > 0 { 1 } else { 0 };
+            Ok(Some(str_range(src, start, start + len.saturating_sub(2))))
+        },
+        e => e
+    }
+}
+
+pub const fn expr_peek_inner_only (src: &str) -> DslPerhaps<&str> {
+    match expr_seek(src) {
+        Err(e) => Err(e),
+        Ok(None) => Ok(None),
+        Ok(Some((start, length))) => {
+            if let Err(e) = no_trailing_non_space(src, start + length, Some("expr_peek_inner_only")) { return Err(e) }
+            let peeked = str_range(src, start, start + length);
+            let len = peeked.len();
+            let start = if len > 0 { 1 } else { 0 };
+            Ok(Some(str_range(peeked, start, start + len.saturating_sub(2))))
+        },
+    }
+}
+
+pub const fn is_word_char (c: char) -> bool {
+    matches!(c, 'a'..='z'|'A'..='Z'|'0'..='9'|'-'|'/'|'@'|':')
+}
+pub const fn is_word_end (c: char) -> bool {
+    is_space(c) || is_expr_end(c)
+}
+dsl_type!(DslWord {
+    fn word (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(word_peek_only))}
+} {
+    pub const fn word_peek      [generated];
+    pub const fn word_peek_only [generated];
+    pub const fn word_seek      [generated];
+    pub const fn word_seek_start (src) {
+        for_each!((i, c) in char_indices(src) => if
+            is_word_char(c)  { return Ok(Some(i)) } else
+            if !is_space(c) { return Err(Unexpected(c, Some(i), Some("word_seek_start"))) });
+        Ok(None)
+    }
+    pub const fn word_seek_length (src) {
+        for_each!((i, c) in char_indices(src) => if !is_word_char(c) { return Ok(Some(i)) });
+        Ok(Some(src.len()))
+    }
+});
+
+pub const fn is_text_start (c: char) -> bool { matches!(c, '"') }
+pub const fn is_text_end (c: char) -> bool { matches!(c, '"') }
+dsl_type!(DslText {
+    fn text (&self) -> DslPerhaps<&str> { ok_flat(self.src()?.map(text_peek_only)) }
+} {
+    pub const fn text_peek      [generated];
+    pub const fn text_peek_only [generated];
+    pub const fn text_seek      [generated];
+    pub const fn text_seek_start (src) {
+        for_each!((i, c) in char_indices(src) =>
+            if is_text_start(c) { return Ok(Some(i)) } else
+            if !is_space(c)     { return Err(Unexpected(c, Some(i), None)) });
+        Ok(None)
+    }
+    pub const fn text_seek_length (src) {
+        for_each!((i, c) in char_indices(src) =>
+            if is_text_end(c) { return Ok(Some(i)) });
+        Ok(None)
+    }
+});
+
+dsl_type!(DslNum {
+    fn num (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(num_peek_only))}
+} {
+    pub const fn num_peek      [generated];
+    pub const fn num_peek_only [generated];
+    pub const fn num_seek      [generated];
+    pub const fn num_seek_start (src) {
+        for_each!((i, c) in char_indices(src) =>
+            if is_digit(c)  { return Ok(Some(i)); } else
+            if !is_space(c) { return Err(Unexpected(c, Some(i), None)) });
+        Ok(None)
+    }
+    pub const fn num_seek_length (src) {
+        for_each!((i, c) in char_indices(src) =>
+            if is_num_end(c) { return Ok(Some(i)) } else
+            if !is_digit(c)  { return Err(Unexpected(c, Some(i), None)) });
+        Ok(None)
+    }
+});
+pub const fn is_digit (c: char) -> bool { matches!(c, '0'..='9') }
+pub const fn is_num_end (c: char) -> bool { matches!(c, ' '|'\n'|'\r'|'\t'|')') }
+pub const fn to_number (digits: &str) -> Result<usize, DslError> {
+    let mut iter = char_indices(digits);
+    let mut value = 0;
+    while let Some(((_, c), next)) = iter.next() {
+        match to_digit(c) {
+            Ok(digit) => value = 10 * value + digit,
+            Err(e) => return Err(e),
+        }
+        iter = next;
+    }
+    Ok(value)
+}
+pub const fn to_digit (c: char) -> Result<usize, DslError> {
+    Ok(match c {
+        '0' => 0, '1' => 1, '2' => 2, '3' => 3, '4' => 4,
+        '5' => 5, '6' => 6, '7' => 7, '8' => 8, '9' => 9,
+        _ => return Err(Unexpected(c, None, Some("parse digit")))
+    })
+}

dsl/src/dsl_ns.rs

@@ -10,18 +10,18 @@ use crate::*;
     // Special form for numeric types
     (num |$state:ident : $State: ty| -> $Type:ty { $( $pat:tt => $body:expr ),* $(,)? }) => {
         impl<'t> DslNs<'t, $Type> for $State {
-            const SYMS: DslNsMap<'t, fn (&'t $State)->Perhaps<$Type>> =
-                DslNsMap::new(&[$(dsl_ns!{@sym ($state: $State) -> $Type { $pat => $body }}),*]);
-            const EXPS: DslNsMap<'t, fn (&'t $State, &str)->Perhaps<$Type>> =
+            const WORDS: DslNsMap<'t, fn (&'t $State)->Perhaps<$Type>> =
+                DslNsMap::new(&[$(dsl_ns!{@word ($state: $State) -> $Type { $pat => $body }}),*]);
+            const EXPRS: DslNsMap<'t, fn (&'t $State, &str)->Perhaps<$Type>> =
                 DslNsMap::new(&[$(dsl_ns!{@exp ($state: $State) -> $Type { $pat => $body }}),*]);
             fn from <D: Dsl> (&'t self, dsl: D) -> Perhaps<$Type> {
                 if let Ok(Some(src)) = dsl.src() {
-                    if let Ok(Some(num)) = src.num() {
-                        Ok(Some(to_number(num)? as $Type))
-                    } else if let Ok(Some(src)) = src.sym() {
-                        self.from_sym(src)
+                    if let Ok(num) = to_number(src) {
+                        Ok(Some(num as $Type))
+                    } else if let Ok(Some(src)) = src.word() {
+                        self.from_word(src)
                     } else {
-                        self.from_exp(src)
+                        self.from_expr(src)
                     }
                 } else {
                     Ok(None)
@@ -36,17 +36,17 @@ use crate::*;
     // Regular form for single type
     (|$state:ident : $State: ty| -> $Type:ty { $( $pat:tt => $body:expr ),* $(,)? }) => {
         impl<'t> DslNs<'t, $Type> for $State {
-            const SYMS: DslNsMap<'t, fn (&'t $State)->Perhaps<$Type>> =
-                DslNsMap::new(&[$(dsl_ns!{@sym ($state: $State) -> $Type { $pat => $body }}),*]);
-            const EXPS: DslNsMap<'t, fn (&'t $State, &str)->Perhaps<$Type>> =
+            const WORDS: DslNsMap<'t, fn (&'t $State)->Perhaps<$Type>> =
+                DslNsMap::new(&[$(dsl_ns!{@word ($state: $State) -> $Type { $pat => $body }}),*]);
+            const EXPRS: DslNsMap<'t, fn (&'t $State, &str)->Perhaps<$Type>> =
                 DslNsMap::new(&[$(dsl_ns!{@exp ($state: $State) -> $Type { $pat => $body }}),*]);
         }
     };
     // Symbols only.
-    (@sym ($state:ident: $State:ty) -> $Type:ty {
-        $sym:literal => $body:expr
+    (@word ($state:ident: $State:ty) -> $Type:ty {
+        $word:literal => $body:expr
     }) => {
-        ($sym, |$state|Ok(Some($body)))
+        ($word, |$state|Ok(Some($body)))
     };
     // Expression handlers only.
     (@exp ($state:ident: $State:ty) -> $Type:ty {
@@ -54,17 +54,21 @@ use crate::*;
     }) => { ($head, |$state, tail: &str|{
         $(
             let head = tail.head()?.unwrap_or_default();
+            let tail = tail.tail()?.unwrap_or_default();
             let $arg: $ty = if let Some(arg) = $state.from(&head)? {
                 arg
             } else {
-                return Err(format!("missing argument: {}", stringify!($arg)).into())
+                return Err(format!("{}: missing argument: {} ({}); got: {tail}",
+                    $head,
+                    stringify!($arg),
+                    stringify!($Type),
+                ).into())
             };
-            let tail = tail.tail()?.unwrap_or_default();
         )*
         Ok(Some($body))
     }) };
     // Nothing else in symbols.
-    (@sym ($state:ident: $State:ty) -> $Type:ty { $pat:tt => $body:expr }) => {
+    (@word ($state:ident: $State:ty) -> $Type:ty { $pat:tt => $body:expr }) => {
         ("", |_|Ok(None)) // FIXME don't emit at all
     };
     // Nothing else in expression handlers.
@@ -75,42 +79,45 @@ use crate::*;
 );
 
 pub trait DslNs<'t, T: 't>: 't {
-    /// Known symbols.
-    const SYMS: DslNsMap<'t, fn (&'t Self)->Perhaps<T>> = DslNsMap::new(&[]);
-    /// Known expressions.
-    const EXPS: DslNsMap<'t, fn (&'t Self, &str)->Perhaps<T>> = DslNsMap::new(&[]);
-    /// Resolve a symbol if known.
-    fn from_sym <D: Dsl> (&'t self, dsl: D) -> Perhaps<T> {
-        if let Some(dsl) = dsl.sym()? {
-            for (sym, get) in Self::SYMS.0 { if dsl == *sym { return get(self) } }
-        }
-        return Ok(None)
-    }
-    /// Resolve an expression if known.
-    fn from_exp <D: Dsl> (&'t self, dsl: D) -> Perhaps<T> {
-        if let Some(exp) = dsl.exp()? {
-            for (key, value) in Self::EXPS.0.iter() {
-                if exp.head() == Ok(Some(key)) { return value(self, exp.tail()?.unwrap_or("")) }
-            }
-        }
-        return Ok(None)
-    }
     /// Resolve an expression or symbol.
     fn from <D: Dsl> (&'t self, dsl: D) -> Perhaps<T> {
         if let Ok(Some(src)) = dsl.src() {
-            if let Ok(Some(src)) = src.sym() {
-                self.from_sym(src)
+            if let Ok(Some(src)) = src.word() {
+                self.from_word(src)
             } else {
-                self.from_exp(src)
+                self.from_expr(src)
             }
         } else {
             Ok(None)
         }
     }
+    /// Resolve a symbol if known.
+    fn from_word <D: Dsl> (&'t self, dsl: D) -> Perhaps<T> {
+        if let Some(dsl) = dsl.word()? {
+            for (word, get) in Self::WORDS.0 { if dsl == *word { return get(self) } }
+        }
+        return Ok(None)
+    }
+    /// Resolve an expression if known.
+    fn from_expr <D: Dsl> (&'t self, dsl: D) -> Perhaps<T> {
+        if let Some(head) = dsl.expr().head()? {
+            for (key, value) in Self::EXPRS.0.iter() {
+                if head == *key {
+                    return value(self, dsl.expr().tail()?.unwrap_or(""))
+                }
+            }
+        }
+        return Ok(None)
+    }
+    /// Known symbols.
+    const WORDS: DslNsMap<'t, fn (&'t Self)->Perhaps<T>> = DslNsMap::new(&[]);
+    /// Known expressions.
+    const EXPRS: DslNsMap<'t, fn (&'t Self, &str)->Perhaps<T>> = DslNsMap::new(&[]);
 }
 /// Namespace mapping.
-pub struct DslNsMap<'t, T: 't>(pub &'t [(&'t str, T)]);
-impl<'t, T: 't> DslNsMap<'t, T> {
+#[derive(Debug)]
+pub struct DslNsMap<'t, T: Debug + 't>(pub &'t [(&'t str, T)]);
+impl<'t, T: Debug + 't> DslNsMap<'t, T> {
     /// Populate a namespace.
     pub const fn new (data: &'t [(&'t str, T)]) -> Self {
         Self(data) // TODO build search index

dsl/src/dsl_type.rs

@@ -1,267 +0,0 @@
-use crate::*;
-
-fn ok_flat <T> (x: Option<DslPerhaps<T>>) -> DslPerhaps<T> {
-    Ok(x.transpose()?.flatten())
-}
-pub const fn is_space (c: char) -> bool {
-    matches!(c, ' '|'\n'|'\r'|'\t')
-}
-pub const fn no_trailing_non_space (
-    src: &str, offset: usize, context: Option<&'static str>
-) -> DslResult<()> {
-    Ok(for_each!((i, c) in char_indices(str_range(src, offset, src.len())) => if !is_space(c) {
-        return Err(Unexpected(c, Some(offset + i), if let Some(context) = context {
-            Some(context)
-        } else {
-            Some("trailing non-space")
-        }))
-    }))
-}
-pub const fn peek (src: &str) -> DslPerhaps<&str> {
-    Ok(Some(if let Ok(Some(exp))  = exp_peek(src)  { exp  } else
-            if let Ok(Some(sym))  = sym_peek(src)  { sym  } else
-            if let Ok(Some(num))  = num_peek(src)  { num  } else
-            if let Ok(Some(text)) = text_peek(src) { text } else
-            if let Err(e) = no_trailing_non_space(src, 0, Some("peek")) { return Err(e) }
-            else { return Ok(None) }))
-}
-pub const fn seek (src: &str) -> DslPerhaps<(usize, usize)> {
-    Ok(Some(if let Ok(Some(exp))  = exp_seek(src)  { exp  } else
-            if let Ok(Some(sym))  = sym_seek(src)  { sym  } else
-            if let Ok(Some(num))  = num_seek(src)  { num  } else
-            if let Ok(Some(text)) = text_seek(src) { text } else
-            if let Err(e) = no_trailing_non_space(src, 0, Some("seek")) { return Err(e) }
-            else { return Ok(None) }))
-}
-pub const fn peek_tail (src: &str) -> DslPerhaps<&str> {
-    match seek(src) {
-        Err(e) => Err(e),
-        Ok(None) => Ok(None),
-        Ok(Some((start, length))) => {
-            let tail = str_range(src, start + length, src.len());
-            for_each!((_i, c) in char_indices(tail) => if !is_space(c) { return Ok(Some(tail)) });
-            Ok(None)
-        },
-    }
-}
-
-#[macro_export] macro_rules! dsl_type (($T:ident { $($trait:tt)* } {
-    pub const fn $peek:ident      $($_1:tt)?;
-    pub const fn $peek_only:ident $($_2:tt)?;
-    pub const fn $seek:ident      $($_3:tt)?;
-    pub const fn $seek_start:ident  ($source1:ident) $body1:block
-    pub const fn $seek_length:ident ($source2:ident) $body2:block
-})=>{
-    pub trait $T: Dsl { $($trait)* }
-    impl<D: Dsl> $T for D {} 
-    /// Find a slice corrensponding to a syntax token.
-    pub const fn $peek (source: &str) -> DslPerhaps<&str> {
-        match $seek(source) {
-            Err(e) => Err(e),
-            Ok(None) => Ok(None),
-            Ok(Some((start, length))) => Ok(Some(str_range(source, start, start + length))),
-        }
-    }
-    /// Find a slice corrensponding to a syntax token
-    /// but return an error if it isn't the only thing
-    /// in the source.
-    pub const fn $peek_only (source: &str) -> DslPerhaps<&str> {
-        match $seek(source) {
-            Err(e) => Err(e),
-            Ok(None) => Ok(None),
-            Ok(Some((start, length))) => {
-                if let Err(e) = no_trailing_non_space(source, start + length, Some("peek_only")) { return Err(e) }
-                Ok(Some(str_range(source, start, start + length)))
-            }
-        }
-    }
-    /// Find a start and length corresponding to a syntax token.
-    pub const fn $seek (source: &str) -> DslPerhaps<(usize, usize)> {
-        match $seek_start(source) {
-            Err(e) => Err(e),
-            Ok(None) => Ok(None),
-            Ok(Some(start)) => match $seek_length(str_from(source, start)) {
-                Ok(Some(length)) => Ok(Some((start, length))),
-                Ok(None) => Ok(None),
-                Err(e) => Err(e),
-            },
-        }
-    }
-    pub const fn $seek_start  ($source1: &str) -> DslPerhaps<usize> $body1
-    pub const fn $seek_length ($source2: &str) -> DslPerhaps<usize> $body2
-});
-
-pub const fn is_exp_start (c: char) -> bool { c == '(' }
-pub const fn is_exp_end (c: char) -> bool { c == ')' }
-dsl_type!(DslExp {
-    fn exp  (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(exp_peek_inner_only))}
-    fn head (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(peek))}
-    fn tail (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(peek_tail))}
-    /// my other car is a cdr :<
-    fn each (&self, mut cb: impl FnMut(&str)->Usually<()>) -> Usually<()> {
-        Ok(if let Some(head) = self.head()? {
-            cb(head)?;
-            if let Some(tail) = self.tail()? {
-                tail.each(cb)?;
-            }
-        })
-    }
-} {
-    pub const fn exp_peek      [generated];
-    pub const fn exp_peek_only [generated];
-    pub const fn exp_seek      [generated];
-    pub const fn exp_seek_start (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_exp_start(c) { return Ok(Some(i)) } else
-            if !is_space(c) { return Err(Unexpected(c, Some(i), Some("expected expression start"))) });
-        Ok(None)
-    }
-    pub const fn exp_seek_length (src) {
-        let mut depth = 0;
-        for_each!((i, c) in char_indices(src) =>
-            if is_exp_start(c) { depth += 1; } else
-            if is_exp_end(c) {
-                if depth == 0 {
-                    return Err(Unexpected(c, Some(i), Some("expected expression end")))
-                } else if depth == 1 {
-                    return Ok(Some(i + 1))
-                } else {
-                    depth -= 1;
-                }
-            });
-        Err(Incomplete)
-    }
-});
-
-pub const fn exp_peek_inner (src: &str) -> DslPerhaps<&str> {
-    match exp_peek(src) {
-        Ok(Some(peeked)) => {
-            let len = peeked.len();
-            let start = if len > 0 { 1 } else { 0 };
-            Ok(Some(str_range(src, start, start + len.saturating_sub(2))))
-        },
-        e => e
-    }
-}
-
-pub const fn exp_peek_inner_only (src: &str) -> DslPerhaps<&str> {
-    match exp_seek(src) {
-        Err(e) => Err(e),
-        Ok(None) => Ok(None),
-        Ok(Some((start, length))) => {
-            if let Err(e) = no_trailing_non_space(src, start + length, Some("exp_peek_inner_only")) { return Err(e) }
-            let peeked = str_range(src, start, start + length);
-            let len = peeked.len();
-            let start = if len > 0 { 1 } else { 0 };
-            Ok(Some(str_range(peeked, start, start + len.saturating_sub(2))))
-        },
-    }
-}
-
-pub const fn is_sym_start (c: char) -> bool { is_sym_char(c) }
-pub const fn is_sym_char (c: char) -> bool { matches!(c, 'a'..='z'|'A'..='Z'|'0'..='9'|'-'|'/'|'@'|':') }
-pub const fn is_sym_end (c: char) -> bool { is_space(c) || is_exp_end(c) }
-dsl_type!(DslSym {
-    fn sym (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(sym_peek_only))}
-} {
-    pub const fn sym_peek      [generated];
-    pub const fn sym_peek_only [generated];
-    pub const fn sym_seek      [generated];
-    pub const fn sym_seek_start (src) {
-        for_each!((i, c) in char_indices(src) => if
-            is_sym_start(c) { return Ok(Some(i)) } else
-            if !is_space(c) { return Err(Unexpected(c, Some(i), Some("sym_seek_start"))) });
-        Ok(None)
-    }
-    pub const fn sym_seek_length (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_sym_end(c) { return Ok(Some(i)) } else
-            if !is_sym_char(c) { return Err(Unexpected(c, Some(i), Some("sym_seek_length"))) });
-        Ok(Some(src.len()))
-    }
-});
-
-pub const fn is_text_start (c: char) -> bool { matches!(c, '"') }
-pub const fn is_text_end (c: char) -> bool { matches!(c, '"') }
-dsl_type!(DslText {
-    fn text (&self) -> DslPerhaps<&str> { ok_flat(self.src()?.map(text_peek_only)) }
-} {
-    pub const fn text_peek      [generated];
-    pub const fn text_peek_only [generated];
-    pub const fn text_seek      [generated];
-    pub const fn text_seek_start (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_text_start(c) { return Ok(Some(i)) } else
-            if !is_space(c)     { return Err(Unexpected(c, Some(i), None)) });
-        Ok(None)
-    }
-    pub const fn text_seek_length (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_text_end(c) { return Ok(Some(i)) });
-        Ok(None)
-    }
-});
-
-pub const fn is_key_start (c: char) -> bool { matches!(c, '/'|('a'..='z')) }
-pub const fn is_key_char (c: char) -> bool { is_key_start(c) || matches!(c, '0'..='9'|'-') }
-pub const fn is_key_end (c: char) -> bool { !is_key_char(c) }
-dsl_type!(DslKey {
-    fn key (&self) -> DslPerhaps<&str> { ok_flat(self.src()?.map(key_peek_only)) }
-} {
-    pub const fn key_peek      [generated];
-    pub const fn key_peek_only [generated];
-    pub const fn key_seek      [generated];
-    pub const fn key_seek_start (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_key_start(c) { return Ok(Some(i)) } else
-            if !is_space(c)    { return Err(Unexpected(c, Some(i), None)) });
-        Ok(None)
-    }
-    pub const fn key_seek_length (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_key_end(c)   { return Ok(Some(i)) } else
-            if !is_key_char(c) { return Err(Unexpected(c, Some(i), None)) });
-        Ok(Some(src.len()))
-    }
-});
-
-dsl_type!(DslNum {
-    fn num (&self) -> DslPerhaps<&str> {ok_flat(self.src()?.map(num_peek_only))}
-} {
-    pub const fn num_peek      [generated];
-    pub const fn num_peek_only [generated];
-    pub const fn num_seek      [generated];
-    pub const fn num_seek_start (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_digit(c)  { return Ok(Some(i)); } else
-            if !is_space(c) { return Err(Unexpected(c, Some(i), None)) });
-        Ok(None)
-    }
-    pub const fn num_seek_length (src) {
-        for_each!((i, c) in char_indices(src) =>
-            if is_num_end(c) { return Ok(Some(i)) } else
-            if !is_digit(c)  { return Err(Unexpected(c, Some(i), None)) });
-        Ok(None)
-    }
-});
-pub const fn is_digit (c: char) -> bool { matches!(c, '0'..='9') }
-pub const fn is_num_end (c: char) -> bool { matches!(c, ' '|'\n'|'\r'|'\t'|')') }
-pub const fn to_number (digits: &str) -> Result<usize, DslError> {
-    let mut iter = char_indices(digits);
-    let mut value = 0;
-    while let Some(((_, c), next)) = iter.next() {
-        match to_digit(c) {
-            Ok(digit) => value = 10 * value + digit,
-            Err(e) => return Err(e),
-        }
-        iter = next;
-    }
-    Ok(value)
-}
-pub const fn to_digit (c: char) -> Result<usize, DslError> {
-    Ok(match c {
-        '0' => 0, '1' => 1, '2' => 2, '3' => 3, '4' => 4,
-        '5' => 5, '6' => 6, '7' => 7, '8' => 8, '9' => 9,
-        _ => return Err(Unexpected(c, None, Some("parse digit")))
-    })
-}

input/src/input_dsl.rs

@@ -1,5 +1,5 @@
 use crate::*;
-use std::{sync::Arc, collections::BTreeMap, path::{Path, PathBuf}, fs::{exists, read_to_string}};
+use std::{sync::Arc, collections::BTreeMap, path::PathBuf};
 /// A collection of input bindings.
 ///
 /// Each contained layer defines a mapping from input event to command invocation

output/src/ops.rs

@@ -511,7 +511,7 @@ transform_xy_unit!("padding/x" "padding/y" "padding/xy"|self: Padding, area|{
 
     ///// The syntagm `(when :condition :content)` corresponds to a [When] layout element.
     //impl<S, A> FromDsl<S> for When<A> where bool: FromDsl<S>, A: FromDsl<S> {
-        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExp>) -> Perhaps<Self> {
+        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExpr>) -> Perhaps<Self> {
             //source.exp_match("when", |_, tail|Ok(Some(Self(
                 //FromDsl::<S>::provide(state,
                     //tail.nth(0, ||"no condition".into())?, ||"no condition".into())?,
@@ -522,7 +522,7 @@ transform_xy_unit!("padding/x" "padding/y" "padding/xy"|self: Padding, area|{
     //}
     ///// The syntagm `(either :condition :content1 :content2)` corresponds to an [Either] layout element.
     //impl<S, A, B> FromDsl<S> for Either<A, B> where S: Eval<Ast, bool> + Eval<Ast, A> + Eval<Ast, B> {
-        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExp>) -> Perhaps<Self> {
+        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExpr>) -> Perhaps<Self> {
             //source.exp_match("either", |_, tail|Ok(Some(Self(
                 //state.eval(tail.nth(0, ||"no condition")?, ||"no condition")?,
                 //state.eval(tail.nth(1, ||"no content 1")?, ||"no content 1")?,
@@ -533,7 +533,7 @@ transform_xy_unit!("padding/x" "padding/y" "padding/xy"|self: Padding, area|{
     ///// The syntagm `(align/* :content)` corresponds to an [Align] layout element,
     ///// where `*` specifies the direction of the alignment.
     //impl<S, A> FromDsl<S> for Align<A> where S: Eval<Option<Ast>, A> {
-        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExp>) -> Perhaps<Self> {
+        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExpr>) -> Perhaps<Self> {
             //source.exp_match("align/", |head, tail|Ok(Some(match head {
                 //"c"  => Self::c(state.eval(tail.nth(0,  ||"no content")?, ||"no content")),
                 //"x"  => Self::x(state.eval(tail.nth(0,  ||"no content")?, ||"no content")),
@@ -553,7 +553,7 @@ transform_xy_unit!("padding/x" "padding/y" "padding/xy"|self: Padding, area|{
     ///// The syntagm `(bsp/* :content1 :content2)` corresponds to a [Bsp] layout element,
     ///// where `*` specifies the direction of the split.
     //impl<S, A, B> FromDsl<S> for Bsp<A, B> where S: Eval<Option<Ast>, A> + Eval<Option<Ast>, B> {
-        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExp>) -> Perhaps<Self> {
+        //fn try_provide (state: &S, source: &DslVal<impl DslStr, impl DslExpr>) -> Perhaps<Self> {
             //source.exp_match("bsp/", |head, tail|Ok(Some(match head {
                 //"n" => Self::n(tail.nth(0, ||"no content 1"), tail.nth(1, ||"no content 2")),
                 //"s" => Self::s(tail.nth(0, ||"no content 1"), tail.nth(1, ||"no content 2")),

proc/src/proc_expose.rs

@@ -87,10 +87,10 @@ impl ExposeImpl {
                 /// Generated by [tengri_proc::expose].
                 impl ::tengri::dsl::FromDsl<#state> for #t {
                     fn from_dsl (state: &#state, dsl: &impl Dsl) -> Perhaps<Self> {
-                        match dsl.key()? {
+                        match dsl.word()? {
                             Some("true")  => Ok(Some(true)),
                             Some("false") => Ok(Some(false)),
-                            _ => match dsl.sym()? { #(#variants)* _ => Ok(None) }
+                            _ => match dsl.word()? { #(#variants)* _ => Ok(None) }
                         }
                     }
                 }
@@ -102,7 +102,7 @@ impl ExposeImpl {
                     fn from_dsl (state: &#state, dsl: &impl Dsl) -> Perhaps<Self> {
                         match dsl.num()? {
                             Some(n) => Ok(Some(n.parse::<#t>()?)),
-                            _ => match dsl.sym()? { #(#variants)* _ => Ok(None) }
+                            _ => match dsl.word()? { #(#variants)* _ => Ok(None) }
                         }
                     }
                 }
@@ -112,7 +112,7 @@ impl ExposeImpl {
                 /// Generated by [tengri_proc::expose].
                 impl ::tengri::dsl::FromDsl<#state> for #t {
                     fn from_dsl (state: &#state, dsl: &impl Dsl) -> Perhaps<Self> {
-                        match dsl.sym()? { #(#variants)* _ => Ok(None) }
+                        match dsl.word()? { #(#variants)* _ => Ok(None) }
                     }
                 }
             }

tui/src/tui_engine/tui_event.rs

@@ -18,14 +18,14 @@ pub struct TuiKey(Option<KeyCode>, KeyModifiers);
 impl TuiKey {
     const SPLIT: char = '/';
     pub fn from_dsl (dsl: impl Dsl) -> Usually<Self> {
-        if let Some(symbol) = dsl.sym()? {
-            let symbol = symbol.trim();
-            Ok(if symbol == ":char" {
+        if let Some(word) = dsl.word()? {
+            let word = word.trim();
+            Ok(if word == ":char" {
                 Self(None, KeyModifiers::NONE)
-            } else if symbol.chars().nth(0) == Some('@') {
+            } else if word.chars().nth(0) == Some('@') {
                 let mut key       = None;
                 let mut modifiers = KeyModifiers::NONE;
-                let mut tokens    = symbol[1..].split(Self::SPLIT).peekable();
+                let mut tokens    = word[1..].split(Self::SPLIT).peekable();
                 while let Some(token) = tokens.next() {
                     if tokens.peek().is_some() {
                         match token {
@@ -47,7 +47,7 @@ impl TuiKey {
                 }
                 Self(key, modifiers)
             } else {
-                return Err(format!("TuiKey: unexpected: {symbol}").into())
+                return Err(format!("TuiKey: unexpected: {word}").into())
             })
         } else {
             return Err(format!("TuiKey: unspecified").into())