Add self-evaluating symbols that start with ":"

src/compiler.cpp

@@ -897,6 +897,23 @@ Result<Expression> Compiler::compile_symbol(Context& context,
                                             const Value& value) {
   Expression ex = TRY(Expression::create());
 
+  // Symbol may be self-evaluating (e.g. :foo), in which case we just use it as
+  // its own value
+
+  if (value.is<Symbol>()) {
+    Symbol& sym = *value.to<Symbol>();
+
+    if (sym.size() > 0 && TRY(sym[0]) == ':') {
+      int64_t c = TRY(context.add_const(value));
+
+      uint64_t reg = context.alloc_reg();
+      TRY(ex.add_opcode(Oc::Mov, {0, (int64_t)reg}, {1, (int64_t)c}));
+
+      ex.reg = reg;
+      return std::move(ex);
+    }
+  }
+
   auto maybe_reg = context.get_var(TRY(value.copy()));
 
   if (!maybe_reg.has_error()) {

test/collections.vli

@@ -9,3 +9,7 @@
 
 (assert (= (get {1 2 3 4} 3)
            4))
+
+;; Accessing collections by symbol
+(assert (= (get {:foo 1 :bar 2} :bar)
+           2))