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javascriptregexace-editor

Find random element with ace.js

How is it possible to find some random element in some code pasted into ace.js editor? Example:

editor.find("<[a-z]+>",{regExp:true});

On a XML-Code like this, the statement will only find the first element 

<root>
   <element1></element1>
   <element2></element2>
   <element3></element3>
</root>

How is it possible to find a random element? e.g. element1, 2 or 3...

BTW: ace.js is providing a way to find all of these elements.

Thank you!

Solution

  • you can find all ranges and pick one of them randomly

    editor.$search.setOptions({needle: "<[a-z]+", regExp:true, preventScroll: true});
ranges = editor.$search.findAll(editor.session)
randomRange = ranges[Math.floor(Math.random() * ranges.length)]
if (randomRange)
    editor.selection.setRange(randomRange)

    or randomly pick starting position

    i = Math.floor(Math.random() * editor.getValue().length)
startPos = editor.session.doc.indexToPosition(i)
editor.find("<[a-z]+",{regExp:true, start: startPos})

    update: the second method isn't good since it's distribution isn't uniform