add docs comment

.verb.md

@@ -8,15 +8,15 @@
 
 **Uses the "bad" `new Function` thing**
 
-I don't think that's a problem, because other template engines out there also uses some kind of `eval` and used massively. Most of them uses `eval`, most of them uses `with`, others of them uses `RegExp`s and etc. They all are with custom non-standard delimiters. They do too much to accomplish same results as `gana`. They requires too big codebase - and finally what, they still uses some of the "bad" things in JS.
+I don't think that's a problem, because other template engines out there also uses some kind of `eval` and it is used massively, believe. Most of them uses `eval`, most of them uses `with`, others of them uses `RegExp`s and etc. They all are with custom non-standard delimiters. They do too much to accomplish same results as `gana`. They requires too big codebase - and finally what, they still uses some of the "bad" things in JS.
 
 **Biggest names uses "bad" things too**
 
 Names such [verb][], [update][], [templates][], [generate][], [assemble][] in our community uses [engine][] - respectively [engine-base][] and/or [engine-cache][]. Not to mention some of the most famous "real" template engines with features like partials, helpers and etc. You can have partials and helpers here in `gana` too.
 
 **Tricking magic**
 
-Behind the scenes `gana` uses [ES2015 (ES6) template strings](https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/template_strings) inside the bad `new Function` which seems to **work even in `node@0.10`** which don't have support for Template Strings! That's strange, but it works and give us that awesome and small codebase (1.39kb, minified and not gzipped) - without any costs.  
+Behind the scenes `gana` uses [ES2015 (ES6) template strings](https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/template_strings) inside the bad `new Function` which seems to **work even in `node@0.10`** which don't have support for Template Strings! That's strange, but it works and give us that awesome and small codebase (**1.39kb, minified and not gzipped**) - without any costs.  
 You just pass normal string `'foo ${bar} and baz'` and then `{ bar: 'bar' }` in the returned function.
 
 **Note about [standard][] (>= v8) users**

README.md

@@ -8,15 +8,15 @@
 
 **Uses the "bad" `new Function` thing**
 
-I don't think that's a problem, because other template engines out there also uses some kind of `eval` and used massively. Most of them uses `eval`, most of them uses `with`, others of them uses `RegExp`s and etc. They all are with custom non-standard delimiters. They do too much to accomplish same results as `gana`. They requires too big codebase - and finally what, they still uses some of the "bad" things in JS.
+I don't think that's a problem, because other template engines out there also uses some kind of `eval` and it is used massively, believe. Most of them uses `eval`, most of them uses `with`, others of them uses `RegExp`s and etc. They all are with custom non-standard delimiters. They do too much to accomplish same results as `gana`. They requires too big codebase - and finally what, they still uses some of the "bad" things in JS.
 
 **Biggest names uses "bad" things too**
 
 Names such [verb][], [update][], [templates][], [generate][], [assemble][] in our community uses [engine][] - respectively [engine-base][] and/or [engine-cache][]. Not to mention some of the most famous "real" template engines with features like partials, helpers and etc. You can have partials and helpers here in `gana` too.
 
 **Tricking magic**
 
-Behind the scenes `gana` uses [ES2015 (ES6) template strings](https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/template_strings) inside the bad `new Function` which seems to **work even in `node@0.10`** which don't have support for Template Strings! That's strange, but it works and give us that awesome and small codebase (1.39kb, minified and not gzipped) - without any costs.  
+Behind the scenes `gana` uses [ES2015 (ES6) template strings](https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/template_strings) inside the bad `new Function` which seems to **work even in `node@0.10`** which don't have support for Template Strings! That's strange, but it works and give us that awesome and small codebase (**1.39kb, minified and not gzipped**) - without any costs.  
 You just pass normal string `'foo ${bar} and baz'` and then `{ bar: 'bar' }` in the returned function.
 
 **Note about [standard][] (>= v8) users**
@@ -35,6 +35,34 @@ npm i gana --save
 const gana = require('gana')
 ```
 
+### [gana](index.js#L40)
+> Compiles a `template` to a function, which accepts `locals` object to populate the template.
+
+**Params**
+
+* `template` **{String}**: string to compile to a function    
+* `returns` **{Function}**: like `compileFn(locals)`, where `locals` must be `object`  
+
+**Example**
+
+```js
+var gana = require('gana')
+
+var template = 'Welcome here, ${ucfirst(name)}! And have fun!'
+var locals = {
+  name: 'charlike',
+  ucfirst: function ucfirst (val) {
+    return val.charAt(0).toUpperCase() + val.slice(1)
+  }
+}
+
+var fn = gana(template)
+var str = fn(locals)
+
+console.log(str)
+// => 'Welcome here, Charlike! And have fun!'
+```
+
 ## Contributing
 Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](https://github.com/tunnckoCore/gana/issues/new).  
 But before doing anything, please read the [CONTRIBUTING.md](./CONTRIBUTING.md) guidelines.

index.js

@@ -8,6 +8,35 @@
 
 var isObject = require('isobject')
 
+/**
+ * > Compiles a `template` to a function, which
+ * accepts `locals` object to populate the template.
+ *
+ * **Example**
+ *
+ * ```js
+ * var gana = require('gana')
+ *
+ * var template = 'Welcome here, ${ucfirst(name)}! And have fun!'
+ * var locals = {
+ *   name: 'charlike',
+ *   ucfirst: function ucfirst (val) {
+ *     return val.charAt(0).toUpperCase() + val.slice(1)
+ *   }
+ * }
+ *
+ * var fn = gana(template)
+ * var str = fn(locals)
+ *
+ * console.log(str)
+ * // => 'Welcome here, Charlike! And have fun!'
+ * ```
+ *
+ * @param  {String} `template` string to compile to a function
+ * @return {Function} like `compileFn(locals)`, where `locals` must be `object`
+ * @api public
+ */
+
 module.exports = function gana (template) {
   if (typeof template !== 'string') {
     throw new TypeError('gana: expect `template` to be a string')