Bar graph added.

node_modules/vega-expression/index.d.ts

@@ -0,0 +1,21 @@
+// TODO: add missing types
+
+export function parse(expression: string): any;
+
+export function codegen(params: {
+  constants?: object;
+  functions?: { [fn: string]: Function };
+  blacklist?: string[];
+  whitelist?: string[];
+  fieldvar?: string;
+  globalvar: string;
+}): (
+  ast: any
+) => {
+  /** The generated code as a string. */
+  code: string;
+  /** A hash of all properties referenced within the fieldvar scope. */
+  fields: string[];
+  /** A hash of all properties referenced outside a provided whitelist */
+  globals: string[];
+};