gistfile1.js

({
    block: 'b-page',
    title: 'index',
    head: [
        { elem: 'css', url: '_index.css', ie: false},
        { elem: 'css', url: '_index.ie.css', ie: true },
        { block: 'i-jquery', elem: 'core'},
        { elem: 'js', url:'_index.js'},
    ],
    content: [
        { block: 'head' }
    ]
})

I'm getting 500 Server Error when I run this json:

HTTP error 500

TypeError: First argument needs to be a number, array or string.
    at new Buffer (buffer.js:188:15)
    at Writer.self.write (/usr/local/lib/node_modules/bem/node_modules/q-io/writer.js:47:23)
    at /usr/local/lib/node_modules/bem/node_modules/q-io/fs-common.js:84:34
    at _fulfilled (/usr/local/lib/node_modules/bem/node_modules/q/q.js:798:54)
    at self.promiseDispatch.done (/usr/local/lib/node_modules/bem/node_modules/q/q.js:827:30)
    at Promise.promise.promiseDispatch (/usr/local/lib/node_modules/bem/node_modules/q/q.js:760:13)
    at /usr/local/lib/node_modules/bem/node_modules/q/q.js:526:49
    at flush (/usr/local/lib/node_modules/bem/node_modules/q/q.js:108:17)
From previous event:
    at Cmd.exports.Cmd.Cmd._do (/usr/local/lib/node_modules/bem/node_modules/coa/lib/cmd.js:424:14)
    at /usr/local/lib/node_modules/bem/node_modules/coa/lib/cmd.js:510:22
    at /usr/local/lib/node_modules/bem/node_modules/coa/node_modules/q/q.js:893:30
    at /usr/local/lib/node_modules/bem/node_modules/coa/node_modules/q/q.js:360:35

For fix 500 Server Error:

@@ -1,5 +1,5 @@
 ({
-    block: 'b-page',
+    block: 'page',