lang/el-compiler/runtime/el_runtime.c

@@ -2242,6 +2242,43 @@ el_val_t url_decode(el_val_t sv) {
     return el_wrap_str(out);
 }
 
+/* ── html_raw ────────────────────────────────────────────────────────────────
+ * Identity passthrough for raw HTML template interpolation.
+ * El's {raw(expr)} compiles to html_raw(expr) — the value is output as-is
+ * without any escaping. The caller is responsible for safety.
+ */
+el_val_t html_raw(el_val_t s) {
+    return s;
+}
+
+/* ── html_escape ─────────────────────────────────────────────────────────────
+ * Escape < > " ' & for safe HTML text interpolation.
+ * El's {expr} in HTML templates compiles to html_escape(expr).
+ */
+el_val_t html_escape(el_val_t sv) {
+    const char* src = EL_CSTR(sv);
+    if (!src) return EL_STR("");
+    size_t len = strlen(src);
+    /* Worst case: every byte → 6 chars (&quot;) */
+    char* out = (char*)malloc(len * 6 + 1);
+    if (!out) return sv;
+    el_arena_track(out);
+    char* p = out;
+    for (size_t i = 0; i < len; i++) {
+        unsigned char c = (unsigned char)src[i];
+        switch (c) {
+            case '&':  memcpy(p, "&amp;",  5); p += 5; break;
+            case '<':  memcpy(p, "&lt;",   4); p += 4; break;
+            case '>':  memcpy(p, "&gt;",   4); p += 4; break;
+            case '"':  memcpy(p, "&quot;", 6); p += 6; break;
+            case '\'': memcpy(p, "&#39;",  5); p += 5; break;
+            default:   *p++ = (char)c;          break;
+        }
+    }
+    *p = '\0';
+    return el_wrap_str(out);
+}
+
 /* ── HTML allowlist sanitizer ────────────────────────────────────────────────
  * el_html_sanitize(input, allowlist_json)
  *

lang/el-compiler/runtime/el_runtime.h

@@ -227,6 +227,8 @@ el_val_t  url_decode(el_val_t s);   /* '+' → space, %XX → byte  */
  *     {"p":[],"a":["href","title"],"strong":[],...}
  * where each value is the array of attribute names allowed for that tag. */
 el_val_t  el_html_sanitize(el_val_t input_html, el_val_t allowlist_json);
+el_val_t  html_raw(el_val_t s);
+el_val_t  html_escape(el_val_t s);
 
 /* ── Filesystem ──────────────────────────────────────────────────────────── */