procedures.js? functions.js? custom-blocks.js?
custom-blocks.js - that way you know that it is definitely about blocks
eg. functions.js could just look like a file containing a few general useful functions
It's in blocks_vertical, so it doesn't need "blocks" in the name.
Went with procedures.js for consistency with Blockly, for now.
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It's in blocks_vertical, so it doesn't need "blocks" in the name.