atom editor

My packages:

    - pretty-json

Insert a carriage return:

    - switch to regexp mode and put \n in the "replace" zone

Select a rectangle

  - If you want to select a rectangular region in atom all you have to do is first set the horizontal dimension by selecting some text, then set the vertical dimension by holding CTL-SHIFT and then pressing the up or down arrow. 

Alternatively you can do this the other way around and set the vertical dimension first with CTL-SHIFT, then let go of CTL but keep holding SHIFT and then use the right or left arrow to select the horizontal dimension.

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