diff --git a/src/forms/syntax.rs b/src/forms/syntax.rs
index 7c27d37..3607621 100644
--- a/src/forms/syntax.rs
+++ b/src/forms/syntax.rs
@@ -11,182 +11,134 @@ pub(crate) struct Syntax {
     pub constants: &'static [&'static str],
 }
 
-/// C, Rust, JavaScript, Go, Java, Swift and kin.
-pub(crate) const C_LIKE: Syntax = Syntax {
-    comment: "//",
-    word_comment: false,
-    keywords: &[
-        "as",
-        "async",
-        "await",
-        "break",
-        "case",
-        "catch",
-        "class",
-        "const",
-        "continue",
-        "do",
-        "else",
-        "enum",
-        "export",
-        "extends",
-        "fn",
-        "for",
-        "from",
-        "func",
-        "function",
-        "if",
-        "impl",
-        "import",
-        "in",
-        "interface",
-        "let",
-        "match",
-        "mut",
-        "new",
-        "package",
-        "pub",
-        "return",
-        "static",
-        "struct",
-        "switch",
-        "throw",
-        "trait",
-        "try",
-        "type",
-        "use",
-        "var",
-        "where",
-        "while",
-        "yield",
-    ],
-    constants: &[
-        "false",
-        "nil",
-        "null",
-        "self",
-        "Self",
-        "this",
-        "true",
-        "undefined",
-        "None",
-        "Some",
-    ],
-};
+impl Syntax {
+    const fn new(
+        comment: &'static str,
+        keywords: &'static [&'static str],
+        constants: &'static [&'static str],
+    ) -> Self {
+        Self {
+            comment,
+            word_comment: false,
+            keywords,
+            constants,
+        }
+    }
+}
 
-const PYTHON: Syntax = Syntax {
-    comment: "#",
-    word_comment: false,
-    keywords: &[
-        "and", "as", "assert", "async", "await", "break", "class", "continue", "def", "del",
-        "elif", "else", "except", "finally", "for", "from", "global", "if", "import", "in", "is",
-        "lambda", "nonlocal", "not", "or", "pass", "raise", "return", "try", "while", "with",
-        "yield",
-    ],
-    constants: &["True", "False", "None", "self"],
-};
+#[rustfmt::skip]
+const RUST: Syntax = Syntax::new("//", &[
+    "as", "async", "await", "break", "const", "continue", "crate", "dyn", "else", "enum", "extern",
+    "fn", "for", "if", "impl", "in", "let", "loop", "match", "mod", "move", "mut", "pub", "ref",
+    "return", "static", "struct", "super", "trait", "type", "unsafe", "use", "where", "while",
+], &["true", "false", "self", "Self", "None", "Some", "Ok", "Err"]);
 
-const SHELL: Syntax = Syntax {
-    comment: "#",
+#[rustfmt::skip]
+const SCRIPT: Syntax = Syntax::new("//", &[
+    "as", "async", "await", "break", "case", "catch", "class", "const", "continue", "default",
+    "delete", "do", "else", "export", "extends", "finally", "for", "from", "function", "if",
+    "import", "in", "instanceof", "interface", "let", "new", "of", "return", "static", "switch",
+    "throw", "try", "type", "typeof", "var", "void", "while", "yield",
+], &["true", "false", "null", "undefined", "this", "NaN"]);
+
+/// C, C++, Java, Go, Swift, Kotlin, C# and kin.
+#[rustfmt::skip]
+pub(crate) const C_LIKE: Syntax = Syntax::new("//", &[
+    "break", "case", "catch", "class", "const", "continue", "default", "defer", "do", "else",
+    "enum", "extends", "final", "for", "func", "fun", "go", "if", "implements", "import",
+    "interface", "let", "namespace", "new", "package", "private", "protected", "public", "return",
+    "static", "struct", "switch", "throw", "try", "typedef", "union", "using", "val", "var",
+    "void", "while",
+], &["true", "false", "null", "nil", "nullptr", "this", "self"]);
+
+#[rustfmt::skip]
+const PYTHON: Syntax = Syntax::new("#", &[
+    "and", "as", "assert", "async", "await", "break", "class", "continue", "def", "del", "elif",
+    "else", "except", "finally", "for", "from", "global", "if", "import", "in", "is", "lambda",
+    "nonlocal", "not", "or", "pass", "raise", "return", "try", "while", "with", "yield",
+], &["True", "False", "None", "self"]);
+
+#[rustfmt::skip]
+const RUBY: Syntax = Syntax::new("#", &[
+    "alias", "and", "begin", "break", "case", "class", "def", "do", "else", "elsif", "end",
+    "ensure", "for", "if", "in", "module", "next", "not", "or", "redo", "rescue", "retry",
+    "return", "then", "unless", "until", "when", "while", "yield",
+], &["true", "false", "nil", "self"]);
+
+#[rustfmt::skip]
+const SHELL: Syntax = Syntax { word_comment: true, ..Syntax::new("#", &[
+    "case", "do", "done", "elif", "else", "esac", "export", "fi", "for", "function", "if", "in",
+    "local", "return", "then", "until", "while",
+], &["true", "false"]) };
+
+/// `#` languages, CMake and Make: no word list.
+const HASH: Syntax = Syntax::new("#", &[], &["true", "false"]);
+
+/// YAML, whose `#` starts a comment only after a space.
+const YAML: Syntax = Syntax {
     word_comment: true,
-    keywords: &[
-        "case", "do", "done", "elif", "else", "esac", "export", "fi", "for", "function", "if",
-        "in", "local", "return", "then", "until", "while",
-    ],
-    constants: &["true", "false"],
+    ..Syntax::new("#", &[], &["true", "false", "null", "yes", "no"])
 };
 
-/// TOML, YAML, INI and other settings: keys are not words.
-const SETTINGS: Syntax = Syntax {
-    comment: "#",
-    word_comment: true,
-    keywords: &[],
-    constants: &["true", "false", "null", "yes", "no", "on", "off"],
-};
+const INI: Syntax = Syntax::new(";", &[], &["true", "false", "yes", "no", "on", "off"]);
 
-const INI: Syntax = Syntax {
-    comment: ";",
-    ..SETTINGS
-};
+#[rustfmt::skip]
+const SQL: Syntax = Syntax::new("--", &[
+    "SELECT", "FROM", "WHERE", "JOIN", "LEFT", "RIGHT", "INNER", "OUTER", "ON", "AND", "OR",
+    "NOT", "AS", "GROUP", "BY", "ORDER", "HAVING", "LIMIT", "OFFSET", "INSERT", "INTO", "VALUES",
+    "UPDATE", "SET", "DELETE", "CREATE", "TABLE", "INDEX", "DROP", "ALTER", "DESC", "ASC",
+    "DISTINCT", "UNION", "WITH", "CASE", "WHEN", "THEN", "ELSE", "END", "IS", "IN", "LIKE",
+    "BETWEEN", "EXISTS",
+], &["NULL", "TRUE", "FALSE"]);
 
-const SQL: Syntax = Syntax {
-    comment: "--",
-    word_comment: false,
-    keywords: &[
-        "SELECT", "FROM", "WHERE", "JOIN", "LEFT", "RIGHT", "INNER", "OUTER", "ON", "AND", "OR",
-        "NOT", "AS", "GROUP", "BY", "ORDER", "HAVING", "LIMIT", "OFFSET", "INSERT", "INTO",
-        "VALUES", "UPDATE", "SET", "DELETE", "CREATE", "TABLE", "INDEX", "DROP", "ALTER", "DESC",
-        "ASC", "DISTINCT", "UNION", "WITH", "CASE", "WHEN", "THEN", "ELSE", "END", "IS", "IN",
-        "LIKE", "BETWEEN", "EXISTS",
-    ],
-    constants: &["NULL", "TRUE", "FALSE"],
-};
+#[rustfmt::skip]
+const LUA: Syntax = Syntax::new("--", &[
+    "and", "break", "do", "else", "elseif", "end", "for", "function", "goto", "if", "in", "local",
+    "not", "or", "repeat", "return", "then", "until", "while",
+], &["true", "false", "nil"]);
 
-const LUA: Syntax = Syntax {
-    comment: "--",
-    word_comment: false,
-    keywords: &[
-        "and", "break", "do", "else", "elseif", "end", "for", "function", "goto", "if", "in",
-        "local", "not", "or", "repeat", "return", "then", "until", "while",
-    ],
-    constants: &["true", "false", "nil"],
-};
+#[rustfmt::skip]
+const HASKELL: Syntax = Syntax::new("--", &[
+    "case", "class", "data", "deriving", "do", "else", "if", "import", "in", "instance", "let",
+    "module", "newtype", "of", "then", "type", "where",
+], &["True", "False"]);
 
-const LISP: Syntax = Syntax {
-    comment: ";",
-    word_comment: false,
-    keywords: &[
-        "defun", "defn", "define", "lambda", "let", "if", "cond", "quote",
-    ],
-    constants: &["nil", "t", "true", "false"],
-};
+#[rustfmt::skip]
+const LISP: Syntax = Syntax::new(";", &[
+    "defun", "defn", "define", "lambda", "let", "if", "cond",
+], &["nil", "t"]);
 
-/// Ruby, Perl, CMake and other `#` languages.
-const HASH: Syntax = Syntax {
-    comment: "#",
-    ..C_LIKE
-};
+#[rustfmt::skip]
+const ERLANG: Syntax = Syntax::new("%", &[
+    "after", "begin", "case", "catch", "end", "fun", "if", "of", "receive", "try", "when",
+], &["true", "false"]);
 
-const TEX: Syntax = Syntax {
-    comment: "%",
-    word_comment: false,
-    keywords: &[],
-    constants: &[],
-};
+const TEX: Syntax = Syntax::new("%", &[], &[]);
 
 /// Extensions of prose and plain text, which read plain.
+#[rustfmt::skip]
 const PROSE: &[&str] = &[
-    "md", "markdown", "mdown", "mkd", "txt", "text", "rst", "adoc", "asciidoc", "org", "csv",
-    "tsv", "log",
+    "md", "markdown", "mdown", "mkd", "txt", "text", "rst", "adoc", "asciidoc", "org", "csv", "tsv",
+    "log",
 ];
 
 /// Languages by extension; any other code reads C-like.
+#[rustfmt::skip]
 const BY_EXTENSION: &[(&Syntax, &[&str])] = &[
+    (&RUST, &["rs"]),
+    (&SCRIPT, &["js", "mjs", "cjs", "jsx", "ts", "tsx", "mts"]),
     (&PYTHON, &["py", "pyi", "pyw"]),
+    (&RUBY, &["rb", "rake", "gemspec"]),
     (&SHELL, &["sh", "bash", "zsh", "fish", "ksh"]),
-    (
-        &HASH,
-        &[
-            "rb", "pl", "r", "cmake", "mk", "nix", "ex", "exs", "jl", "nim", "cr", "tcl", "ps1",
-        ],
-    ),
-    (
-        &SETTINGS,
-        &[
-            "toml",
-            "yaml",
-            "yml",
-            "conf",
-            "cfg",
-            "gitignore",
-            "env",
-            "properties",
-        ],
-    ),
+    (&HASH, &["pl", "r", "cmake", "mk", "nix", "ex", "exs", "jl", "nim", "cr", "tcl", "ps1",
+        "toml", "conf", "cfg", "gitignore", "env", "properties"]),
+    (&YAML, &["yaml", "yml"]),
     (&INI, &["ini"]),
     (&SQL, &["sql"]),
     (&LUA, &["lua"]),
+    (&HASKELL, &["hs", "lhs", "elm"]),
     (&LISP, &["clj", "cljs", "lisp", "el", "scm"]),
+    (&ERLANG, &["erl", "hrl"]),
     (&TEX, &["tex", "sty", "bib"]),
 ];
 
@@ -195,13 +147,10 @@ pub(crate) fn syntax_of(path: &str) -> Option<&'static Syntax> {
     let name = path.rsplit_once('/').map_or(path, |(_, name)| name);
     // Named files first: CMakeLists.txt is not prose.
     match name {
-        "Makefile" | "GNUmakefile" | "Dockerfile" | "CMakeLists.txt" => return Some(&SHELL),
+        "Makefile" | "GNUmakefile" | "Dockerfile" | "CMakeLists.txt" => return Some(&HASH),
         _ => {}
     }
-    let ext = match name.rsplit_once('.') {
-        Some((_, ext)) => ext.to_ascii_lowercase(),
-        None => return None,
-    };
+    let ext = name.rsplit_once('.')?.1.to_ascii_lowercase();
     if PROSE.contains(&ext.as_str()) {
         return None;
     }
diff --git a/src/git/rows.rs b/src/git/rows.rs
index 711f8c1..9ff1847 100644
--- a/src/git/rows.rs
+++ b/src/git/rows.rs
@@ -184,6 +184,34 @@ mod tests {
                 Some(syntax.keyword),
                 "a TOML key"
             );
+            // Words belong to their own language.
+            assert_ne!(
+                color("let from = 42;", "main.rs", cx)[1].1,
+                Some(syntax.keyword),
+                "Rust's from"
+            );
+            assert_eq!(
+                color("def hello", "a.rb", cx)[0].1,
+                Some(syntax.keyword),
+                "Ruby's def"
+            );
+            assert_eq!(
+                color("-- return 42", "Main.hs", cx),
+                [(0..12, Some(syntax.comment))]
+            );
+            assert_eq!(
+                color("% return 42", "main.erl", cx),
+                [(0..11, Some(syntax.comment))]
+            );
+            // A comment may follow code at once outside Shell.
+            assert_eq!(
+                color("answer = 42# return 99", "config.toml", cx).last(),
+                Some(&(11..22, Some(syntax.comment)))
+            );
+            assert_eq!(
+                color("set(x 1)# return 42", "CMakeLists.txt", cx).last(),
+                Some(&(8..19, Some(syntax.comment)))
+            );
             // Shell comments start words only.
             let shell = color("echo foo#bar 42", "run.sh", cx);
             assert!(