Introduce "special" query kind

src/collector.js

@@ -86,8 +86,10 @@ export default class Collector {
         // TODO: warning.
         invariant(result.kind !== 'unknown');
 
-        // Resulting scope is always the best choice for waiting.
-        scope = result.scope;
+        if (result.kind !== 'special') {
+            // Resulting scope is always the best choice for waiting.
+            scope = result.scope;
+        }
 
         // It's only valid the sequence: E*[CT]?F,
         //     where E - external, C - declaration, T - template, F - definition.
@@ -141,6 +143,13 @@ export default class Collector {
                 // Fallthrough.
             case 'definition':
                 return result.type;
+
+            case 'special':
+                const type = result.call(params);
+
+                invariant(type);
+
+                return type;
         }
 
         invariant(false);

src/globals.js

@@ -1,7 +1,8 @@
-export default [
-    {
-        id: ['Buffer'],
-        kind: 'record',
-        fields: [],
+export default {
+    Buffer() {
+        return {
+            kind: 'reference',
+            to: ["Buffer"],
+        };
     },
-];
+}

src/query.js

@@ -8,7 +8,8 @@ export type Query =
     | Declaration
     | Template
     | Definition
-    | External;
+    | External
+    | Special;
 
 export type Unknown = {
     kind: 'unknown',
@@ -42,6 +43,13 @@ export type External = {
     scope: Scope,
 };
 
+export type Special = {
+    kind: 'special',
+    call: SpecialFn,
+};
+
+export type SpecialFn = (?Type)[] => ?Type;
+
 export type TemplateParam = {
     name: string,
     value: ?Type,

src/scope.js

@@ -4,7 +4,7 @@ import type {Node} from '@babel/types';
 import {invariant, last} from './utils';
 import type Module from './module';
 import type {Type, TypeId} from './types';
-import type {Query, Template, TemplateParam, ExternalInfo} from './query';
+import type {Query, Template, TemplateParam, ExternalInfo, SpecialFn} from './query';
 
 export default class Scope {
     +id: TypeId;
@@ -12,16 +12,13 @@ export default class Scope {
     +module: ?Module;
     _entries: Map<string, Query>;
 
-    static global(types: Type[]) {
+    static global(specials: {[string]: SpecialFn}) {
         const global = new Scope(null, null);
 
-        for (const type of types) {
-            invariant(type.id);
+        for (const name in specials) {
+            const fn = specials[name];
 
-            const name = last(type.id);
-            invariant(name != null);
-
-            global.addDefinition(name, type, false);
+            global.addSpecial(name, fn);
         }
 
         return global;
@@ -38,6 +35,15 @@ export default class Scope {
         return new Scope(this, module || this.module);
     }
 
+    addSpecial(name: string, fn: SpecialFn) {
+        invariant(!this._entries.has(name));
+
+        this._entries.set(name, {
+            kind: 'special',
+            call: fn,
+        });
+    }
+
     addDeclaration(name: string, node: Node, params: TemplateParam[]) {
         invariant(!this._entries.has(name));