metric

Learn about the metric extension point.

Heads up!

When writing conditions, be sure to use floating-point numbers. For example, use "== 8.0" instead of "== 8".

Name	Type	Description
formula	string	A formula of pre-defined variables to be evaluated.
condition	string	A binary condition upon which formula will trigger an alert.

metric enforces arbitrary formulas based on pre-defined, built-in variables.

extends: metric
message: 'Try to keep the Flesch-Kincaid grade level (%s) below 8.'
link: |
  https://en.wikipedia.org/wiki/Flesch%E2%80%93Kincaid_readability_tests

formula: |
  (0.39 * (words / sentences)) + (11.8 * (syllables / words)) - 15.59

condition: '> 8.0'

Variables

The table below summarizes all available variables:

Variable	Description
blockquote	The number of blockquote tags.
characters	The number of characters.
complex_words	The number of polysyllabic words without common suffixes (es, ed, ing, …).
heading.h{n}	The number of headings at the specified level (for example, heading.h1).
list	The number of ol and ul tags.
long_words	The number of words with more than 6 characters.
paragraphs	The number of paragraphs.
polysyllabic_words	The number of words with more than 2 syllables.
pre	The number of pre tags.
sentences	The number of sentences.
syllables	The number of syllables.
words	The number of words.

Since the pre-defined variables are calculated using the entire document, all metric-based rules are summary-scoped.

Operators

In addition to using the variables listed above, a formula may also use the following operators:

Operator	Description
+	Addition
-	Subtraction
*	Multiplication
/	Division
math.sqrt(x)	Square root of x
math.abs(x)	Absolute value of x

A condition may use one of >, <, ==, >=, and <=.

message

The result of a formula will be compared to its condition and inserted into its message format specifier (%s).

capitalization spelling