Update dependencies, fix up Cargo.toml

Besides code cleanup, this commit changes the sanitization logic to
avoid numeric digits altogether. Previously, they had been allowed at
the end of a label name, but this is susceptible to a ZZT parser bug:
`#foo` matches `:foo2` because ZZT allows a prefix match if the next
character is a digit.

Cargo.lock

@@ -10,9 +10,9 @@ checksum = "e16d2d3311acee920a9eb8d33b8cbc1787ce4a264e85f964c2404b969bdcd487"
 
 [[package]]
 name = "castaway"
-version = "0.2.3"
+version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0abae9be0aaf9ea96a3b1b8b1b55c602ca751eba1b1500220cea4ecbafe7c0d5"
+checksum = "dec551ab6e7578819132c713a93c022a05d60159dc86e7a7050223577484c55a"
 dependencies = [
  "rustversion",
 ]
@@ -138,8 +138,8 @@ dependencies = [
  "compact_str",
  "insta",
  "lexopt",
+ "mzp-peg-macro",
  "nom",
- "peg_macro",
  "rustc-hash",
 ]
 
@@ -150,29 +150,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32a282da65faaf38286cf3be983213fcf1d2e2a58700e808f83f4ea9a4804bc0"
 
 [[package]]
-name = "minimal-lexical"
+name = "mzp-peg-macro"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
-
-[[package]]
-name = "nom"
-version = "7.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
-dependencies = [
- "memchr",
- "minimal-lexical",
-]
-
-[[package]]
-name = "once_cell"
-version = "1.21.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
-
-[[package]]
-name = "peg_macro"
 version = "0.1.0"
 dependencies = [
  "itertools",
@@ -181,6 +159,21 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "nom"
+version = "8.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df9761775871bdef83bee530e60050f7e54b1105350d6884eb0fb4f46c2f9405"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "once_cell"
+version = "1.21.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.95"

Cargo.toml

@@ -1,16 +1,20 @@
 [package]
 name = "marzipan"
+description = "A macro processor for ZZT worlds"
+keywords = ["zzt", "gamedev"]
+categories = ["compilers", "command-line-utilities"]
 version = "0.1.0"
 edition = "2024"
+license = "MIT"
+repository = "https://github.com/cmounce/marzipan"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
 anyhow = "1.0.86"
 codepage-437 = "0.1.0"
-peg_macro = { path = "./peg_macro"}
+mzp-peg-macro = { path = "./mzp_peg_macro", version = "0.1.0" }
-insta = "1.39.0"
+nom = "8.0.0"
-nom = "7.1.3"
 compact_str = "0.9.0"
 rustc-hash = "2.1.1"
 lexopt = "0.3.1"
@@ -22,9 +26,5 @@ insta = "1.39.0"
 insta.opt-level = 3
 similar.opt-level = 3
 
-[[bin]]
-name = "marzipan"
-path = "src/main.rs"
-
 [workspace]
-members = [".", "peg_macro"]
+members = [".", "mzp_peg_macro"]

LICENSE

@@ -0,0 +1,18 @@
+MIT License
+
+Copyright (c) 2025 Chris Mounce
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the
+following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
+LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
+EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+USE OR OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -0,0 +1,57 @@
+# Marzipan
+Marzipan is a macro processor for [ZZT](https://en.wikipedia.org/wiki/ZZT).
+It extends the ZZT-OOP scripting language while still maintaining compatibility with ZZT 3.2: all language features compile down to vanilla ZZT-OOP.
+
+## Features
+- **Anonymous labels:** Like assembly code, ZZT-OOP control flow relies heavily on gotos.
+    Anonymous labels reduce the cognitive overhead of writing such code.
+    `:@` defines a label with a unique name, and `@f`/`@b` reference the nearest anonymous label forward/backward of the current line.
+- **Local labels:** Label names with a dot are scoped to a single section of an object's program.
+    This allows you to reuse a name like `.loop` multiple times in a single object's code.
+    Marzipan will replace this with a distinct name per section: `loop_` in one section, `loopa` in the next section, etc.
+- **Macro language (WIP):** Lines starting with `%` invoke a Marzipan macro.
+    Macros work by text substitution; for example, `%include "foo.txt"` will insert the contents of a text file at the current line.
+
+Here's an example of what anonymous labels look like in practice:
+
+```
+@Treasure chest
+#end
+:touch                  'Event handler, user touched the chest.
+#if key @f              'Jump to anonymous label. Marzipan compiles `@f` to `_`...
+The chest is locked.
+#end
+:@                      '...and compiles this to `:_`.
+You unlock the chest.
+There's a bunch of gems inside!
+#give gems 20
+#die
+
+:shot                   'Event handler, user shot at the chest.
+#if shotgun @f          'This time, Marzipan compiles `@f` to `a`...
+Nothing happens.
+#end
+:@                      '...and compiles this to `:a`.
+The chest shatters!
+Gems fly everywhere.
+#put w green gem
+#put e green gem
+#become green gem
+```
+
+## Usage
+Marzipan reads and writes ZZT world files, a binary file format.
+You will need either ZZT itself or an external ZZT editor (such as [KevEdit](https://github.com/cknave/kevedit)) to work with them.
+
+```
+marzipan WORLD.ZZT -o ./dest_folder/WORLD.ZZT
+```
+
+A disclaimer: **Marzipan is experimental.**
+It hasn't eaten my code yet, but I cannot guarantee it will treat your code with kindness.
+If you use it, make sure to keep backups of your work. (You were already keeping backups, right?)
+
+## Planned features
+- Extending the macro system to a full language with variables, custom macro definitions, etc.
+- Code minification, for generated code that bumps up against ZZT 3.2's size limits.
+- Lints for ZZT-OOP, such as dead code analysis.

mzp_peg_macro/Cargo.toml

@@ -1,7 +1,10 @@
 [package]
-name = "peg_macro"
+name = "mzp-peg-macro"
+description = "Internal crate for generating Marzipan's PEG parser code"
 version = "0.1.0"
 edition = "2024"
+license = "MIT"
+repository = "https://github.com/cmounce/marzipan"
 
 [lib]
 proc-macro = true

mzp_peg_macro/README.md

@@ -0,0 +1,5 @@
+A PEG parser generator built for [Marzipan](https://github.com/cmounce/marzipan).
+
+Currently tightly coupled to Marzipan's specific needs and not designed for general use.
+It might evolve into a standalone library in the future if there's broader interest.
+But until then, you probably want something like [pest](https://pest.rs/) if you're looking for a PEG parser.

src/encoding.rs

@@ -1,7 +1,8 @@
 use anyhow::{Result, anyhow};
 use codepage_437::CP437_WINGDINGS;
 
-// Serialize multi-line content with CR-terminated lines
+/// Serialize a multi-line code string for an object or a scroll.
+/// Uses ZZT's convention of CR-terminated lines.
 pub fn encode_multiline(input: &str) -> Result<Vec<u8>> {
     input
         .chars()
@@ -17,6 +18,7 @@ pub fn encode_multiline(input: &str) -> Result<Vec<u8>> {
         .collect()
 }
 
+/// Deserialize a multi-line code string.
 pub fn decode_multiline(input: &[u8]) -> String {
     input
         .iter()
@@ -30,6 +32,8 @@ pub fn decode_multiline(input: &[u8]) -> String {
         .collect()
 }
 
+/// Serialize a single-line string for a board title.
+/// Newlines cannot be encoded because ZZT interprets them as dingbats (♪).
 pub fn encode_oneline(input: &str) -> Result<Vec<u8>> {
     input
         .chars()
@@ -41,6 +45,7 @@ pub fn encode_oneline(input: &str) -> Result<Vec<u8>> {
         .collect()
 }
 
+/// Deserialize a board title.
 pub fn decode_oneline(input: &[u8]) -> String {
     input.iter().map(|&x| CP437_WINGDINGS.decode(x)).collect()
 }
@@ -86,12 +91,12 @@ mod tests {
     }
 
     #[test]
-    fn byte_13_to_wingding() {
+    fn byte_13_to_dingbat() {
         // Code is allowed to have newlines
         let bytes = serialize_code("ABC\nDEF");
         assert!(bytes.contains(&13));
 
-        // But in a board title, that same byte is a wingding
+        // But in a board title, that same byte is a dingbat
         assert_debug_snapshot!(decode_oneline(&bytes), @r#""ABC♪DEF""#);
     }
 

src/error.rs

@@ -75,6 +75,13 @@ impl<'a> Context<'a> {
         });
     }
 
+    pub fn any_errors(&self) -> bool {
+        match self {
+            Context::Base(refcell) => refcell.borrow().iter().any(|x| x.level == Level::Error),
+            Context::With(parent, _info) => parent.any_errors(),
+        }
+    }
+
     pub fn into_messages(self) -> Vec<CompileMessage> {
         match self {
             Context::Base(refcell) => {
@@ -102,7 +109,7 @@ pub struct CompileMessage {
     pub location: Location,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Eq, PartialEq)]
 pub enum Level {
     Error,
     Warning,

src/labels/parse.rs

@@ -121,7 +121,7 @@ pub fn parse_stat_labels(stat: &Stat, ctx: &Context) -> ParsedStat {
 }
 
 mod grammar {
-    use peg_macro::grammar;
+    use mzp_peg_macro::grammar;
 
     grammar! {
         program = (line ("\n" line)*)? EOI;

src/labels/process.rs

@@ -8,7 +8,7 @@ use super::{
     sanitize::Registry,
 };
 
-pub fn process_labels(board: &Board, ctx: &Context) -> Board {
+pub fn process_labels(board: &Board, ctx: &Context) -> Option<Board> {
     let mut board = board.clone();
 
     // Parse stats into chunks
@@ -20,10 +20,17 @@ pub fn process_labels(board: &Board, ctx: &Context) -> Board {
         .collect();
     let mut registry = Registry::new();
 
+    // Expand ".local" labels to full "section.local" form.
     resolve_local_labels(&mut stats, ctx);
-    assign_named_labels(&mut stats, &mut registry);
 
-    // Assign names to anonymous labels
+    // Sanitize all non-anonymous labels.
+    // This condenses name strings like "namespace~name$1.local" down to
+    // something short and valid for ZZT-OOP, e.g., "local_".
+    sanitize_named_labels(&mut stats, &mut registry);
+
+    // Replace anonymous labels with short names.
+    // This happens after sanitization so we know which short names are available to use.
+    // Two passes are needed because anonymous references can point either forward or backward.
     anonymous_forward_pass(&mut stats, &mut registry, ctx);
     anonymous_backward_pass(&mut stats, ctx);
 
@@ -43,7 +50,7 @@ pub fn process_labels(board: &Board, ctx: &Context) -> Board {
         old_stat.code = new_code;
     }
 
-    board
+    (!ctx.any_errors()).then_some(board)
 }
 
 /// Resolve ".local" labels to "name.local" form.
@@ -51,15 +58,8 @@ fn resolve_local_labels(stats: &mut [ParsedStat], ctx: &Context) {
     for (i, stat) in stats.iter_mut().enumerate() {
         let ctx = ctx.with_stat(i);
 
-        // Helper: Generate unique section strings like "touch$0"
+        // Keep a separate resolver for each namespace
-        let mut i = 0;
+        let mut resolvers: FxHashMap<Option<CompactString>, LocalLabelResolver> =
-        let mut make_section_id = |label_name: &str| -> CompactString {
-            let result = format!("{}${}", &label_name, i);
-            i += 1;
-            result.into()
-        };
-
-        let mut namespace_to_section: FxHashMap<Option<CompactString>, CompactString> =
             FxHashMap::default();
 
         for chunk in stat.iter_mut() {
@@ -69,33 +69,22 @@ fn resolve_local_labels(stats: &mut [ParsedStat], ctx: &Context) {
                     is_anon: false,
                     name: label,
                 } => {
-                    // Handle cases where either one of (section name, label) is missing.
+                    let resolver = resolvers.entry(label.namespace.clone()).or_default();
-                    // If both are present ("name.local") then the label is already fully resolved
+                    let is_definition = !*is_ref;
-                    // and there is nothing to do.
+                    if let Some(local) = &label.local {
-                    if label.name.is_empty() {
+                        if label.name.is_empty() {
-                        // Expand :.local to :name.local
+                            // Local that needs to be resolved, such as ":.foo" or "#send .foo"
-                        assert!(label.local.is_some());
+                            label.name = resolver.get_section_prefix(&local)
-                        label.name = if let Some(section) =
+                        } else if is_definition {
-                            namespace_to_section.get(&label.namespace)
+                            // Illegal local label definition, such as ":touch.foo"
-                        {
+                            // _References_ to local labels may specify a section name: "#send touch.foo".
-                            section.clone()
+                            // But when a local is _defined_, the section name must always be inferred.
-                        } else {
+                            ctx.with_span(label.span.clone())
-                            let section = make_section_id("");
+                                .error("local label definitions cannot specify a section name");
-                            namespace_to_section.insert(label.namespace.clone(), section.clone());
-                            section
                         }
-                    } else if label.local.is_none() {
+                    } else if is_definition {
-                        // Interpret label :name as start of new section.
+                        // Top-level label definition, such as ":touch"
-                        // Only label definitions do this; label references have no effect.
+                        resolver.start_new_section(&label.name);
-                        if !*is_ref {
-                            namespace_to_section
-                                .insert(label.namespace.clone(), make_section_id(&label.name));
-                        }
-                    } else {
-                        // User specified both a section name and a local name ("name.local").
-                        // This isn't allowed because of issues around resolving the section ID.
-                        ctx.with_span(label.span.clone())
-                            .error("local labels with section names not supported");
                     }
                 }
                 _ => {}
@@ -104,8 +93,59 @@ fn resolve_local_labels(stats: &mut [ParsedStat], ctx: &Context) {
     }
 }
 
+#[derive(Default)]
+struct LocalLabelResolver {
+    current_section: CompactString,
+    current_section_index: usize,
+    pair_info: FxHashMap<(CompactString, CompactString), LocalLabelInfo>,
+}
+
+struct LocalLabelInfo {
+    last_section_index: usize,
+    num_sections: usize,
+}
+
+impl<'a> LocalLabelResolver {
+    /// Record the start of a new section, e.g., `touch`.
+    ///
+    /// This is called for each occurence of a top-level label; if the same
+    /// label name appears multiple times, that creates multiple sections.
+    fn start_new_section(&mut self, section: &str) {
+        self.current_section = section.into();
+        self.current_section_index += 1;
+    }
+
+    /// Generate a distinct section string (e.g., `touch$1`) for a local label.
+    ///
+    /// The output depends not just on the section's and local's names, but also
+    /// the number of previous sections that have had that section-local combo:
+    ///
+    /// - The first time `.foo` appears in a `touch` section, all instances of
+    ///     `.foo` within that section resolve to `touch.foo`.
+    /// - But if there's a _second_ `touch` label, any instances of `.foo` within
+    ///     _that_ section must resolve to a distinct name: `touch$1.foo`.
+    fn get_section_prefix(&mut self, local: &str) -> CompactString {
+        let key = (self.current_section.clone(), local.into());
+        let info = self.pair_info.entry(key).or_insert_with(|| LocalLabelInfo {
+            last_section_index: self.current_section_index,
+            num_sections: 1,
+        });
+        if info.last_section_index != self.current_section_index {
+            info.last_section_index = self.current_section_index;
+            info.num_sections += 1;
+        }
+        let mut result = self.current_section.clone();
+        if info.num_sections > 1 {
+            let disambiguator = info.num_sections - 1;
+            result.push('$');
+            result.push_str(&disambiguator.to_string());
+        }
+        result
+    }
+}
+
 /// Assign sanitized names to all of the named labels.
-fn assign_named_labels(stats: &mut [ParsedStat], registry: &mut Registry) {
+fn sanitize_named_labels(stats: &mut [ParsedStat], registry: &mut Registry) {
     for stat in stats.iter_mut() {
         for chunk in stat.iter_mut() {
             match chunk {
@@ -140,6 +180,8 @@ fn anonymous_forward_pass(stats: &mut [ParsedStat], registry: &mut Registry, ctx
     let mut label_names = vec![];
 
     for (stat_index, stat) in stats.iter_mut().enumerate() {
+        let ctx = ctx.with_stat(stat_index);
+
         // Helper: Get the next label name that hasn't been used in this object yet
         let mut i = 0;
         let mut get_next_name = || -> CompactString {
@@ -155,7 +197,6 @@ fn anonymous_forward_pass(stats: &mut [ParsedStat], registry: &mut Registry, ctx
         let mut namespace_to_latest: FxHashMap<Option<CompactString>, CompactString> =
             FxHashMap::default();
 
-        let ctx = ctx.with_stat(stat_index);
         for chunk in stat.iter_mut() {
             match chunk {
                 Chunk::Label {
@@ -190,8 +231,9 @@ fn anonymous_forward_pass(stats: &mut [ParsedStat], registry: &mut Registry, ctx
 /// Resolve anonymous forward references to their label names.
 fn anonymous_backward_pass(stats: &mut [ParsedStat], ctx: &Context) {
     for (stat_index, stat) in stats.iter_mut().enumerate() {
-        let mut namespace_to_latest = FxHashMap::default();
         let ctx = ctx.with_stat(stat_index);
+
+        let mut namespace_to_latest = FxHashMap::default();
         for chunk in stat.iter_mut().rev() {
             match chunk {
                 Chunk::Label {
@@ -276,28 +318,28 @@ mod test {
     #[test]
     fn test_label_sanitization() {
         let board = board_from_text("tests/labels/sanitize.txt");
-        let board = process_labels(&board, &Context::new());
+        let board = process_labels(&board, &Context::new()).unwrap();
         assert_snapshot!(board_to_text(board));
     }
 
     #[test]
     fn test_anonymous_labels() {
         let board = board_from_text("tests/labels/anonymous.txt");
-        let board = process_labels(&board, &Context::new());
+        let board = process_labels(&board, &Context::new()).unwrap();
         assert_snapshot!(board_to_text(board));
     }
 
     #[test]
     fn test_local_labels() {
         let board = board_from_text("tests/labels/local.txt");
-        let board = process_labels(&board, &Context::new());
+        let board = process_labels(&board, &Context::new()).unwrap();
         assert_snapshot!(board_to_text(board));
     }
 
     #[test]
     fn test_namespaces() {
         let board = board_from_text("tests/labels/namespaces.txt");
-        let board = process_labels(&board, &Context::new());
+        let board = process_labels(&board, &Context::new()).unwrap();
         assert_snapshot!(board_to_text(board));
     }
 

src/labels/sanitize.rs

@@ -1,187 +1,151 @@
-use std::collections::{HashMap, HashSet};
-
 use compact_str::CompactString;
+use rustc_hash::{FxHashMap, FxHashSet};
 
-#[derive(PartialEq, Eq, Hash)]
+pub struct Registry {
-struct LabelId(CompactString);
+    key_to_suffix: FxHashMap<Lowercase, Suffix>,
+    names: FxHashSet<Lowercase>,
+    anonymous_counter: CompactString,
+}
 
-impl LabelId {
+#[derive(Clone, PartialEq, Eq, Hash)]
-    fn new(label: &str) -> Self {
+struct Lowercase(CompactString);
-        let mut result = CompactString::new(label);
+
+impl Lowercase {
+    fn new(key: &str) -> Self {
+        let mut result = CompactString::new(key);
         result.make_ascii_lowercase();
         Self(result)
     }
 }
 
-pub struct Registry {
+#[derive(Default)]
-    label_transforms: HashMap<LabelId, Transform>,
+struct Suffix(CompactString);
-    existing: HashSet<CompactString>,
-    anonymous_counter: CompactString,
-}
 
-enum Transform {
+impl Suffix {
-    Preferred,
+    fn apply(&self, key: &str) -> CompactString {
-    FilteredWithSuffix(CompactString),
+        let mut result = preferred_label_name(key);
-}
+        result.push_str(&self.0);
-
+        result
-impl Transform {
-    fn apply(&self, label: &str) -> CompactString {
-        let preferred = preferred_label_name(label);
-        match self {
-            Transform::Preferred => preferred,
-            Transform::FilteredWithSuffix(suffix) => {
-                let mut result = preferred;
-                result = Registry::filter_label_chars(&result);
-                result.push_str(&suffix);
-                result
-            }
-        }
     }
 }
 
 impl Registry {
     pub fn new() -> Self {
         let builtin_labels = ["bombed", "energize", "shot", "thud", "touch"];
-        let mut label_transforms = HashMap::new();
+        let mut key_to_suffix = FxHashMap::default();
-        let mut existing = HashSet::new();
+        let mut taken = FxHashSet::default();
         for name in builtin_labels {
-            let cs = CompactString::new(name);
+            let name = Lowercase(name.into());
-            label_transforms.insert(LabelId(cs.clone()), Transform::Preferred);
+            key_to_suffix.insert(name.clone(), Suffix::default());
-            existing.insert(cs);
+            taken.insert(name);
         }
         Self {
-            label_transforms,
+            key_to_suffix,
-            existing,
+            names: taken,
-            anonymous_counter: "_".into(),
+            anonymous_counter: CompactString::const_new(""),
         }
     }
 
-    pub fn sanitize(&mut self, label: &str) -> CompactString {
+    pub fn sanitize(&mut self, key: &str) -> CompactString {
         // Use existing sanitization if one exists
-        let id = LabelId::new(label);
+        let key_lower = Lowercase::new(key);
-        if let Some(transform) = self.label_transforms.get(&id) {
+        if let Some(transform) = self.key_to_suffix.get(&key_lower) {
-            return transform.apply(label);
+            return transform.apply(key);
         }
 
-        // Try to use label's preferred name as-is
+        // Append suffixes until we find a name that's not taken yet
-        let preferred = Transform::Preferred.apply(label);
+        let mut candidate = Lowercase::new(&preferred_label_name(key));
-        if Registry::is_valid_label(&preferred) {
+        let mut suffix = CompactString::const_new("");
-            let key = preferred.to_ascii_lowercase();
+        let original_len = candidate.0.len();
-            if !self.existing.contains(&key) {
-                self.label_transforms.insert(id, Transform::Preferred);
-                self.existing.insert(key);
-                return preferred;
-            }
-        }
-
-        // Generate a new name by appending suffixes
-        let base = Registry::filter_label_chars(&preferred);
-        let base_len = base.len();
-        let mut candidate = base;
-        let mut suffix = CompactString::with_capacity(0);
         loop {
-            candidate.push_str(&suffix);
+            candidate.0.push_str(&suffix);
-            let key = candidate.to_ascii_lowercase();
+            if !self.names.contains(&candidate) {
-            if !self.existing.contains(&key) {
+                self.key_to_suffix.insert(key_lower, Suffix(suffix));
-                self.label_transforms
+                self.names.insert(candidate.clone());
-                    .insert(id, Transform::FilteredWithSuffix(suffix));
-                self.existing.insert(key);
                 break;
             } else {
-                candidate.truncate(base_len);
+                candidate.0.truncate(original_len);
                 increment(&mut suffix);
             }
         }
-        candidate
+        candidate.0
     }
 
     pub fn gen_anonymous(&mut self) -> CompactString {
-        while self.existing.contains(&self.anonymous_counter) {
+        increment(&mut self.anonymous_counter);
+        while self
+            .names
+            .contains(&Lowercase(self.anonymous_counter.clone()))
+        {
             increment(&mut self.anonymous_counter);
         }
-        let result = self.anonymous_counter.clone();
+        self.anonymous_counter.clone()
-        increment(&mut self.anonymous_counter);
-        result
-    }
-
-    fn is_valid_label(s: &CompactString) -> bool {
-        if s.len() == 0 {
-            return false;
-        }
-        let (most, last) = s.split_at(s.len() - 1);
-        if !most.chars().all(|c| c == '_' || c.is_ascii_alphabetic()) {
-            return false;
-        }
-        last.chars().all(|c| c == '_' || c.is_ascii_alphanumeric())
-    }
-
-    fn filter_label_chars(s: &CompactString) -> CompactString {
-        let mut result = CompactString::with_capacity(0);
-        let mut run_of_digits = false;
-        for c in s.chars() {
-            if c.is_ascii_digit() {
-                if !run_of_digits {
-                    result.push('_');
-                    run_of_digits = true;
-                }
-            } else {
-                result.push(c);
-                run_of_digits = false;
-            }
-        }
-        result
     }
 }
 
-/// Given an unsanitized full name, generate the first-pick name we'd like to
+/// Given the key string identifying a label, generate the first-pick name we'd
-/// assign this label. (Results returned by this function are subject to veto
+/// like to assign it. (Results returned by this function are subject to veto if
-/// if they are invalid or already taken.)
+/// they are already taken.)
-fn preferred_label_name(s: &str) -> CompactString {
+fn preferred_label_name(key: &str) -> CompactString {
-    if let Some((_, suffix)) = s.rsplit_once(|c: char| !c.is_ascii_alphanumeric() && c != '_') {
+    // Extract the last part of the key: "ns~global$123.local" becomes "local"
-        // Prevent namespaces and local labels from starting with a digit.
+    let base_name = key
-        // This ensures stuff like `#take gems 100.99orless` won't compile
+        .rsplit_once(|c: char| !c.is_ascii_alphanumeric() && c != '_')
-        // to `#take gems 10099orless` (would parse incorrectly).
+        .map(|(_, base_name)| base_name)
-        let mut result = CompactString::const_new("_");
+        .unwrap_or(key);
-        result.push_str(suffix);
+
-        result
+    // Collapse runs of numeric digits/underscores to a single underscore
-    } else {
+    let mut result = CompactString::default();
-        CompactString::new(s)
+    let mut run = false;
+    for c in base_name.chars() {
+        if c.is_ascii_alphabetic() {
+            result.push(c);
+            run = false;
+        } else if !run {
+            result.push('_');
+            run = true;
+        }
     }
+    result
 }
 
 /// Increments a string through label-safe characters.
-/// Characters loop through underscore and the letters a-z.
+///
-/// Additionally, the final character is allowed to loop through 0-9.
+/// The characters tick upward in order (underscore, a-z), odometer style,
+/// growing the string on overflow. The result is similar to counting in
+/// base 27, but it's not quite the same:
+///
+/// - The zeroth value is the empty string "" (not "_").
+/// - "z" is followed by "__", "_a", "_b", etc (not "a_", "aa", "ab").
+///
+/// Unlike in place-value systems where "0001" and "1" are equivalent, the goal
+/// of this function is to generate every possible string.
 fn increment(s: &mut CompactString) {
     let original_len = s.len();
 
     // Find a character we can increment without carry
     let mut last_char = s.pop();
-    while !(last_char == None || last_char != Some('z')) {
+    while last_char == Some('z') {
         last_char = s.pop();
     }
 
     if let Some(c) = last_char {
-        // Increment character in order: 0-9, then _, then a-z
+        // Increment character
         let incremented = match c {
-            '0'..'9' | 'a'..'z' => (c as u8 + 1) as char,
+            'a'..'z' => (c as u8 + 1) as char,
-            '9' => '_',
             '_' => 'a',
             _ => unreachable!(),
         };
         s.push(incremented);
 
-        // Pad to original length, like "___0"
+        // Pad to original length
         while s.len() < original_len {
-            let is_last = s.len() == original_len - 1;
-            s.push(if is_last { '0' } else { '_' });
-        }
-    } else {
-        // We reached maximum value for the string: everything rolls over
-        for _ in 0..original_len {
             s.push('_');
         }
-        s.push('0');
+    } else {
+        // All existing chars roll over, length grows by 1
+        for _ in 0..(original_len + 1) {
+            s.push('_');
+        }
     }
 }
 
@@ -210,29 +174,26 @@ mod test {
         }
         let result = rows.join("\n");
         assert_snapshot!(result, @r"
-        0, 1, 2, 3, 4, 5, 6, 7, 8, 9
         _, a, b, c, d, e, f, g, h, i
         j, k, l, m, n, o, p, q, r, s
-        t, u, v, w, x, y, z, _0, _1, _2
+        t, u, v, w, x, y, z, __, _a, _b
-        _3, _4, _5, _6, _7, _8, _9, __, _a, _b
         _c, _d, _e, _f, _g, _h, _i, _j, _k, _l
         _m, _n, _o, _p, _q, _r, _s, _t, _u, _v
-        _w, _x, _y, _z, a0, a1, a2, a3, a4, a5
+        _w, _x, _y, _z, a_, aa, ab, ac, ad, ae
-        a6, a7, a8, a9, a_, aa, ab, ac, ad, ae
         af, ag, ah, ai, aj, ak, al, am, an, ao
+        ap, aq, ar, as, at, au, av, aw, ax, ay
+        az, b_, ba, bb, bc, bd, be, bf, bg, bh
+        bi, bj, bk, bl, bm, bn, bo, bp, bq, br
         ");
     }
 
     #[test]
     fn test_increment_all_len_3() {
-        // Most chars are alphabetic or underscore (26 + 1 = 27).
+        let num_labels = 27 + 27 * 27 + 27 * 27 * 27; // 1 char + 2 chars + 3 chars
-        // Last char can include digits (27 + 10 = 37).
-        let num_labels = 37 + 27 * 37 + 27 * 27 * 37; // 1 char + 2 chars + 3 chars
         let mut ctr = CompactString::new("");
         let mut seen = HashSet::with_capacity(num_labels);
         for _ in 0..num_labels {
             increment(&mut ctr);
-            assert!(Registry::is_valid_label(&ctr));
             assert!(!seen.contains(&ctr));
             assert!(ctr.len() <= 3);
             seen.insert(ctr.clone());
@@ -273,20 +234,20 @@ mod test {
         let result = results.join("\n");
         assert_snapshot!(result, @r#"
         "foo" => foo
-        "ns1~foo" => _foo
+        "ns1~foo" => foo_
-        "ns2~foo" => _foo0
+        "ns2~foo" => fooa
-        "foo.thisloop" => _thisloop
+        "foo.thisloop" => thisloop
-        "foo.thatloop" => _thatloop
+        "foo.thatloop" => thatloop
-        "bar.thisloop" => _thisloop0
+        "bar.thisloop" => thisloop_
-        "bar.thatloop" => _thatloop0
+        "bar.thatloop" => thatloop_
-        "foo$1.thisloop" => _thisloop1
+        "foo$1.thisloop" => thisloopa
-        "foo$1.thatloop" => _thatloop1
+        "foo$1.thatloop" => thatloopa
-        "bar1" => bar1
+        "bar1" => bar_
-        "bar2" => bar2
+        "bar2" => bar__
-        "bar123" => bar_
+        "bar123" => bar_a
-        "BAR123" => BAR_
+        "BAR123" => BAR_a
-        "bar456" => bar_0
+        "bar456" => bar_b
-        "BAR456" => BAR_0
+        "BAR456" => BAR_b
         "foo2bar" => foo_bar
         "#);
     }

src/labels/snapshots/marzipan__labels__process__test__diagnostics.snap

@@ -82,12 +82,11 @@ error: message targets not supported for local labels
  7 | :.local
    |
 
-error: local labels with section names not supported
+error: local label definitions cannot specify a section name
- => test.zzt -> Title screen -> @Locals with section names (1,1) -> line 3:2
+ => test.zzt -> Title screen -> @Local label definitions with section names (1,1) -> line 8:2
    |
- 1 | @Locals with section names
+ 5 | #touch.skip
- 2 | :touch
+ 6 | '
- 3 | #touch.skip
+ 7 | 'this is not
+ 8 | :touch.skip
    |  ^^^^^^^^^^
- 4 | :.skip
-   |

src/labels/snapshots/marzipan__labels__process__test__label_sanitization.snap

@@ -9,14 +9,14 @@ expression: board_to_text(board)
 You have hundreds of gems.
 #end
 :lt_
-#take gems 10 lt_0
+#take gems 10 lt__
 #give gems 10
 You have tens of gems.
 #end
-:lt_0
+:lt__
-#take gems 1 lt1
+#take gems 1 lt_a
 #give gems 1
 You have at least one gem.
 #end
-:lt1
+:lt_a
 You don't have any gems!

src/labels/snapshots/marzipan__labels__process__test__local_labels.snap

@@ -6,50 +6,77 @@ expression: board_to_text(board)
 'using the same local label ".loop"
 :run_w
 #walk w
-:_loop
+:loop
 #try w stop
-#_loop
+#loop
 '
 :run_e
 #walk e
-:_loop0
+:loop_
 #try e stop
-#_loop0
+#loop_
 '
 :stop
 #walk i
 ---
 'Using locals before any globals are defined
-:_loop1
+:loopa
-#take gems 1 _break
+#take gems 1 break
-#_loop1
+#loopa
-:_break
+:break
 ---
 'Multiple sections with the same name
 #end
 :touch
 Trying to sell you some ammo...
-#take gems 10 _skip
+#take gems 10 skip
 #give ammo 10
-:_skip
+:skip
 #zap touch
 #end
 :touch
 Trying to sell you some torches...
-#take gems 15 _skip0
+#take gems 15 skip_
 #give torches 5
-:_skip0
+:skip_
 #restore touch
 ---
 'Multiple locals with the same name
 #end
-:repeat3
+:repeat_
-:_z
+:z
-:_z
+:z
-:_z
+:z
-#take gems 1 _skip1
+#take gems 1 skipa
 #give score 1
-:_skip1
+:skipa
-#zap _z
+#zap z
-#_z
+#z
-:_z
+:z
+---
+'Addressing labels with section.local
+:touch
+:foo
+#end
+:touch
+:foo_
+#end
+:shot
+'sends to the first one:
+#foo
+---
+@alice
+:shared
+'this is the 1st section named "shared"
+'but its local should correspond with @bob's 2nd "shared"
+:local
+#end
+:shared
+---
+@bob
+:shared
+#end
+:shared
+'this is the 2nd section named "shared"
+'but its local should correspond with @alice's 1st "shared"
+:local

src/labels/snapshots/marzipan__labels__process__test__namespaces.snap

@@ -22,13 +22,13 @@ expression: board_to_text(board)
 'Make sure locals exist in separate namespaces
 :do_stuff
 #lock
-:_loop
+:loop
 '
-:_do_stuff
+:do_stuff_
-:_loop0
+:loop_
-/i#if blocked rndne _loop0
+/i#if blocked rndne loop_
 '
-#take time 1 _break
+#take time 1 break
-#_loop
+#loop
-:_break
+:break
 #unlock

src/main.rs

@@ -84,7 +84,9 @@ fn main() -> Result<()> {
     let ctx = base_ctx.with_file_path(&input_filename);
     for (i, board) in world.boards.iter_mut().enumerate() {
         let ctx = ctx.with_board(i);
-        *board = process_labels(&board, &ctx);
+        if let Some(processed_board) = process_labels(&board, &ctx) {
+            *board = processed_board;
+        }
     }
 
     // Print diagnostics

src/peg/peg.rs

@@ -207,7 +207,7 @@ impl<'a, T: Clone> Capture<'a, T> {
 #[cfg(test)]
 mod tests {
     use insta::assert_debug_snapshot;
-    use peg_macro::grammar;
+    use mzp_peg_macro::grammar;
 
     use super::ParseState;
 

src/world.rs

@@ -7,7 +7,6 @@ use nom::{
     error::{ErrorKind, ParseError},
     multi::count,
     number::complete::{le_i16, le_u8, le_u16},
-    sequence::tuple,
 };
 
 use crate::encoding::{decode_multiline, decode_oneline, encode_multiline, encode_oneline};
@@ -128,14 +127,13 @@ pub struct Stat {
 
 impl World {
     pub fn from_bytes(bytes: &[u8]) -> Result<World, LoadError> {
-        let (input, (_, num_boards)) = tuple((tag([0xff, 0xff]), le_i16)).parse(bytes)?;
+        let (input, (_, num_boards)) = (tag(&[0xff, 0xff][..]), le_i16).parse(bytes)?;
-        let (input, (ammo, gems, keys)) =
+        let (input, (ammo, gems, keys)) = (le_i16, le_i16, count(bool_u8, 7)).parse(input)?;
-            tuple((le_i16, le_i16, count(bool_u8, 7))).parse(input)?;
         let (input, (health, starting_board, torches, torch_cycles, energizer_cycles)) =
-            tuple((le_i16, le_i16, le_i16, le_i16, le_i16)).parse(input)?;
+            (le_i16, le_i16, le_i16, le_i16, le_i16).parse(input)?;
-        let (input, (_, score, world_name)) = tuple((take(2usize), le_i16, pstring(20)))(input)?;
+        let (input, (_, score, world_name)) = (take(2usize), le_i16, pstring(20)).parse(input)?;
         let (input, flags) = count(pstring(20), 10).parse(input)?;
-        let (_input, (time, time_ticks, locked)) = tuple((le_i16, le_i16, bool_u8)).parse(input)?;
+        let (_input, (time, time_ticks, locked)) = (le_i16, le_i16, bool_u8).parse(input)?;
 
         // Rest of header is padding; fast-forward starting from original input
         let (input, _) = take(512usize).parse(bytes)?;
@@ -214,7 +212,7 @@ impl Board {
         let mut input = input;
         let mut terrain = Vec::with_capacity(NUM_TILES);
         while terrain.len() < NUM_TILES {
-            let (next_input, (count, element, color)) = tuple((le_u8, le_u8, le_u8))(input)?;
+            let (next_input, (count, element, color)) = (le_u8, le_u8, le_u8).parse(input)?;
             input = next_input;
             let count: u32 = if count == 0 { 256 } else { count.into() };
             for _ in 0..count {
@@ -226,11 +224,11 @@ impl Board {
         }
 
         // Read board info
-        let (input, (max_shots, is_dark)) = tuple((le_u8, bool_u8))(input)?;
+        let (input, (max_shots, is_dark)) = (le_u8, bool_u8).parse(input)?;
         let (input, (board_n, board_s, board_w, board_e)) =
-            tuple((le_u8, le_u8, le_u8, le_u8))(input)?;
+            (le_u8, le_u8, le_u8, le_u8).parse(input)?;
-        let (input, (reenter_when_zapped, message)) = tuple((bool_u8, pstring(58)))(input)?;
+        let (input, (reenter_when_zapped, message)) = (bool_u8, pstring(58)).parse(input)?;
-        let (input, (enter_x, enter_y, time_limit)) = tuple((le_u8, le_u8, le_i16))(input)?;
+        let (input, (enter_x, enter_y, time_limit)) = (le_u8, le_u8, le_i16).parse(input)?;
         let (input, _) = take(16usize)(input)?;
 
         // Read stats
@@ -239,7 +237,7 @@ impl Board {
         if num_stats < 0 {
             return Err("cannot have a negative number of stats".into());
         }
-        let (_input, stats) = count(Stat::from_bytes, num_stats as usize)(input)?;
+        let (_input, stats) = count(Stat::from_bytes, num_stats as usize).parse(input)?;
 
         Ok(Board {
             name,
@@ -315,12 +313,12 @@ impl Board {
 
 impl Stat {
     pub fn from_bytes(input: &[u8]) -> IResult<&[u8], Self, LoadError> {
-        let (input, (x, y, x_step, y_step)) = tuple((le_u8, le_u8, le_i16, le_i16))(input)?;
+        let (input, (x, y, x_step, y_step)) = (le_u8, le_u8, le_i16, le_i16).parse(input)?;
-        let (input, (cycle, p1, p2, p3)) = tuple((le_i16, le_u8, le_u8, le_u8))(input)?;
+        let (input, (cycle, p1, p2, p3)) = (le_i16, le_u8, le_u8, le_u8).parse(input)?;
-        let (input, (follower, leader)) = tuple((le_i16, le_i16))(input)?;
+        let (input, (follower, leader)) = (le_i16, le_i16).parse(input)?;
-        let (input, (under_element, under_color)) = tuple((le_u8, le_u8))(input)?;
+        let (input, (under_element, under_color)) = (le_u8, le_u8).parse(input)?;
         let (input, _) = take(4usize)(input)?;
-        let (input, (instruction_pointer, length)) = tuple((le_i16, le_i16))(input)?;
+        let (input, (instruction_pointer, length)) = (le_i16, le_i16).parse(input)?;
         let (input, _) = take(8usize)(input)?;
         let (input, code_bytes) = take(0.max(length) as usize)(input)?;
         let code = decode_multiline(&code_bytes);
@@ -363,15 +361,15 @@ impl Stat {
         result.push_padding(4);
         result.push_i16(self.instruction_pointer);
         // TODO: more safety around valid bind-indexes (positive? negative?)
+        let code_bytes = encode_multiline(&self.code).unwrap();
         result.push_i16(if self.bind_index < 0 {
             self.bind_index
         } else {
-            self.code.len() as i16
+            code_bytes.len() as i16
         });
         result.push_padding(8);
         if self.bind_index >= 0 {
             // TODO: more safety around bind-index XOR code
-            let code_bytes = encode_multiline(&self.code).unwrap();
             result.extend_from_slice(&code_bytes);
         }
         result
@@ -387,7 +385,7 @@ fn pstring(cap: u8) -> impl Fn(&[u8]) -> IResult<&[u8], Vec<u8>, LoadError> {
     move |input: &[u8]| -> IResult<&[u8], Vec<u8>, LoadError> {
         let (input, len) = le_u8(input)?;
         if len >= cap {
-            return fail(input);
+            return fail().parse(input);
         }
         let (input, data) = take(len)(input)?;
         let (input, _) = take(cap - len)(input)?;

tests/labels/diagnostics.txt

@@ -23,7 +23,11 @@
 :@
 :.local
 ---
-@Locals with section names
+@Local label definitions with section names
+'these are okay
 :touch
-#touch.skip
 :.skip
+#touch.skip
+'
+'this is not
+:touch.skip

tests/labels/local.txt

@@ -49,4 +49,30 @@ Trying to sell you some torches...
 #zap .z
 #.z
 :.z
-
+---
+'Addressing labels with section.local
+:touch
+:.foo
+#end
+:touch
+:.foo
+#end
+:shot
+'sends to the first one:
+#touch.foo
+---
+@alice
+:shared
+'this is the 1st section named "shared"
+'but its local should correspond with @bob's 2nd "shared"
+:.local
+#end
+:shared
+---
+@bob
+:shared
+#end
+:shared
+'this is the 2nd section named "shared"
+'but its local should correspond with @alice's 1st "shared"
+:.local