From 632e4a1bc51ee86b3f0a55e95ee78def391aab30 Mon Sep 17 00:00:00 2001
From: "Dylan M. Taylor" <dylan@dylanmtaylor.com>
Date: Tue, 3 Nov 2026 22:57:52 -0500
Subject: [PATCH] formula, calc: LET/LAMBDA names looked up through a map;
 ragged array literals refused before reserving (#3312)

---
 crates/calc/src/eval.rs     |  5 ++++
 crates/formula/src/input.rs | 48 ++++++++++++++++++++++++++++++++-----
 2 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/crates/calc/src/eval.rs b/crates/calc/src/eval.rs
index 7a957f3a4..7f10354da 100644
--- a/crates/calc/src/eval.rs
+++ b/crates/calc/src/eval.rs
@@ -325,6 +325,11 @@ impl<'h> Evaluator<'h> {
             Expr::Array(rows) => {
                 let h = rows.len();
                 let w = rows.first().map_or(0, Vec::len);
+                // A ragged literal is an error either way; one wide row and many empty ones must
+                // not reserve their rows-times-width product first.
+                if rows.iter().any(|row| row.len() != w) {
+                    return err(CellError::Value);
+                }
                 let mut data = Vec::with_capacity(h * w);
                 for row in rows {
                     for el in row {
diff --git a/crates/formula/src/input.rs b/crates/formula/src/input.rs
index 1c8929739..6d95587a7 100644
--- a/crates/formula/src/input.rs
+++ b/crates/formula/src/input.rs
@@ -61,7 +61,7 @@ impl FormulaLocale {
 pub fn parse_input(src: &str, locale: FormulaLocale, known_name: impl Fn(&str) -> bool) -> Result<Expr, ParseError> {
     let mut expr = parser::parse_syntax(src, locale)?;
     if locale == FormulaLocale::Es {
-        normalize(&mut expr, &known_name, &mut Vec::new(), 0, false)?;
+        normalize(&mut expr, &known_name, &mut Bindings::default(), 0, false)?;
     }
     Ok(expr)
 }
@@ -96,7 +96,7 @@ pub fn print_input(expr: &Expr, locale: FormulaLocale, known_name: impl Fn(&str)
         return Ok(crate::print(expr));
     }
     let mut expr = expr.clone();
-    normalize(&mut expr, &known_name, &mut Vec::new(), 0, true)?;
+    normalize(&mut expr, &known_name, &mut Bindings::default(), 0, true)?;
     let canonical = crate::print(&expr);
     let tokens = crate::lexer::tokenize(&canonical).map_err(|e| ParseError { msg: e.msg, pos: e.pos })?;
     let mut out = String::new();
@@ -131,11 +131,47 @@ pub(crate) fn boolean_alias(name: &str) -> Option<bool> {
     }
 }
 
-fn normalize(expr: &mut Expr, known_name: &impl Fn(&str) -> bool, bindings: &mut Vec<String>, depth: usize, display: bool) -> Result<(), ParseError> {
+/// The LET/LAMBDA names in scope, with how many times each is bound, so a lookup is one probe
+/// instead of a scan of every binding for each call.
+#[derive(Default)]
+struct Bindings {
+    stack: Vec<String>,
+    counts: std::collections::HashMap<String, usize>,
+}
+
+impl Bindings {
+    fn len(&self) -> usize {
+        self.stack.len()
+    }
+
+    fn push(&mut self, name: &str) {
+        let key = crate::fold_name(name);
+        *self.counts.entry(key.clone()).or_default() += 1;
+        self.stack.push(key);
+    }
+
+    fn truncate(&mut self, len: usize) {
+        while self.stack.len() > len {
+            let Some(key) = self.stack.pop() else { break };
+            if let Some(n) = self.counts.get_mut(&key) {
+                *n -= 1;
+                if *n == 0 {
+                    self.counts.remove(&key);
+                }
+            }
+        }
+    }
+
+    fn contains(&self, name: &str) -> bool {
+        self.counts.contains_key(&crate::fold_name(name))
+    }
+}
+
+fn normalize(expr: &mut Expr, known_name: &impl Fn(&str) -> bool, bindings: &mut Bindings, depth: usize, display: bool) -> Result<(), ParseError> {
     if depth > parser::MAX_DEPTH {
         return Err(ParseError { msg: "formula is nested too deeply".into(), pos: 0 });
     }
-    let bound = |name: &str, bindings: &[String]| bindings.iter().rev().any(|n| crate::same_name(n, name)) || known_name(name);
+    let bound = |name: &str, bindings: &Bindings| bindings.contains(name) || known_name(name);
     match expr {
         Expr::Bool(value) if display => {
             let alias = if *value { "VERDADERO" } else { "FALSO" };
@@ -156,7 +192,7 @@ fn normalize(expr: &mut Expr, known_name: &impl Fn(&str) -> bool, bindings: &mut
                         // The new name is not in scope in its own value expression.
                         normalize(value, known_name, bindings, depth + 1, display)?;
                         if let Expr::Name(name) = declaration {
-                            bindings.push(name.clone());
+                            bindings.push(name);
                         }
                     }
                 }
@@ -169,7 +205,7 @@ fn normalize(expr: &mut Expr, known_name: &impl Fn(&str) -> bool, bindings: &mut
             if let Some((body, params)) = args.split_last_mut() {
                 for param in params {
                     if let Expr::Name(name) = param {
-                        bindings.push(name.clone());
+                        bindings.push(name);
                     }
                 }
                 normalize(body, known_name, bindings, depth + 1, display)?;