The 'extract_completions' method seams to have a bug when it comes to variables that contain one or more dashes.
$button_color_main: #0f0 /* works as expected */
$button-color-secondary: #f00 /* will auto complete only the word '$button' */
The bug is double checked and confirmed, more here: https://github.com/alienhard/SublimeAllAutocomplete/issues/18
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