Miscellaneous `sym.rs` improvements (#5045)

crates/typst/src/symbols/sym.rs

@@ -100,8 +100,8 @@ pub(crate) const SYM: &[(&str, Symbol)] = symbols! {
     dash: [
         #[call(crate::math::accent::dash)] en: '–',
         em: '—',
-        em.two: '\u{2e3a}',
-        em.three: '\u{2e3b}',
+        em.two: '⸺',
+        em.three: '⸻',
         fig: '‒',
         wave: '〜',
         colon: '∹',
@@ -129,7 +129,7 @@ pub(crate) const SYM: &[(&str, Symbol)] = symbols! {
     pilcrow: ['¶', rev: '⁋'],
     section: '§',
     semi: [';', rev: '⁏'],
-    slash: ['/', double: '⫽', triple: '⫻', big: '\u{29f8}'],
+    slash: ['/', double: '⫽', triple: '⫻', big: '⧸'],
     dots: [h.c: '⋯', h: '…', v: '⋮', down: '⋱', up: '⋰'],
     tilde: [
         #[call(crate::math::accent::tilde)] op: '∼',
@@ -944,6 +944,9 @@ pub(crate) const SYM: &[(&str, Symbol)] = symbols! {
     Zeta: 'Ζ',
 
     // Hebrew.
+    // In math, the following symbols are replaced with corresponding characters
+    // from Letterlike Symbols.
+    // See https://github.com/typst/typst/pull/3375.
     aleph: 'א',
     alef: 'א',
     beth: 'ב',