First-class functions & negative calc

• BREAKING: Remove all non-essential default sizes
• BUGFIX: Add convert-units to local (pre-captured) functions
• NEW: negative function can be used with calc() values,
  returning calc(-1 * (<value>))
• NEW: $functions map allows you to name/capture first-class functions
  in the latest versions of Sass, and call them by name in the $sizes map
• NEW: add-sizes & add-ratios functions can be used
  to merge partial maps into the global $sizes/$ratios maps

v5.0.2

• BUGFIX: Fix implicit division in map values

Remove Warnings

• BUGFIX: negative and square functions handle units properly

5.0 - Breaking Bugfix & New Features

• BREAKING: $from-context defaults to 'root' when available
• BUGFIX: Browser-em math requires $from-context
• NEW: Allow size() function to accept additional arguments
  (e.g. $from-context and $to-context) for unit-conversion.
• NEW: Allow convert-units function to accept named sizes
  for all length values.

Publish styleguide documentation

• Publish missing styleguide documentation.

4.0!

Same as 4.0.0-alpha-1 - 09/06/17

• BREAKING: Remove overly-opinionated baseline type tools
  including font-size and baseline mixins.
  These settings are more clear when established explicitly in CSS
• BREAKING: Rename scale() => ratio() to avoid conflicts with CSS
• BREAKING: Remove stand-alone browser-ems() function…
• NEW: Allow browser-ems as a $to-unit argument
  in the contert-units() function.
• NEW: Add (private) pow() functions,
  so that MathSass is no longer a dependency for non-integer steps

4.0 Alpha 1

• BREAKING: Remove overly-opinionated baseline type tools
  including font-size and baseline mixins.
  These settings are more clear when established explicitly in CSS
• BREAKING: Rename scale() => ratio() to avoid conflicts with CSS
• BREAKING: Remove stand-alone browser-ems() function…
• NEW: Allow browser-ems as a $to-unit argument
  in the contert-units() function.
• NEW: Add (private) pow() functions,
  so that MathSass is no longer a dependency for non-integer steps

Public `scale()` function

• NEW: Rename private _get-ratio() to public scale() for consistent access to ratios with map-key references.

calc-reference bugfix

• BUGFIX: Resolve problems with referencing calc() values

Explicit unit-handling, and get-function support

• BREAKING: Don't convert units unless specifically requested.
  This allows you to define preferred units per-item
  in the configuration map.
• BREAKING: Remove $default-units setting. See above.
• Allow arbitrary adjustment functions
  in the $sizes map,
  e.g. 'my-size': 24px ('add': 12px),
  where add is an available function
  that will accept 24px, 12px as arguments.
• Support first-class functions in Sass 3.5.