Module: Metanorma::Mirror::MathUtil

Defined in:
lib/metanorma/mirror/math_util.rb

Overview

MathUtil is the single home for math-content extraction helpers.

These helpers convert mathML XML objects into strings (stripped of XML declarations) and extract asciimath from stem elements. They are used by handlers and renderers that need to carry math content through the mirror pipeline.

Class Method Summary collapse

Class Method Details

.asciimath_from_stem(stem) ⇒ Object

Extract asciimath text from a stem element. Returns nil if no asciimath is present.



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# File 'lib/metanorma/mirror/math_util.rb', line 26

def self.asciimath_from_stem(stem)
  asciimath = SafeAttr.read(stem, :asciimath)
  return nil unless asciimath.is_a?(Array)

  parts = asciimath.filter_map do |a|
    next a if a.is_a?(String)
    next SafeAttr.read(a, :text).to_s if a.is_a?(Lutaml::Model::Serializable)

    nil
  end
  joined = parts.join.strip
  joined.empty? ? nil : joined
end

.mathml_from_math(math) ⇒ Object 



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# File 'lib/metanorma/mirror/math_util.rb', line 19

def self.mathml_from_math(math)
  xml = math.is_a?(Array) ? math.map(&:to_xml).join : math.to_xml
  strip_xml_decl(xml)
end

.strip_xml_decl(math_xml) ⇒ Object 



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# File 'lib/metanorma/mirror/math_util.rb', line 15

def self.strip_xml_decl(math_xml)
  math_xml.sub(STRIP_XML_DECL_PATTERN, "")
end

.text_from_stem(stem) ⇒ Object

Best-effort plain-text extraction from a stem element. Tries asciimath first; falls back to SafeAttr :text.



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# File 'lib/metanorma/mirror/math_util.rb', line 42

def self.text_from_stem(stem)
  asciimath = asciimath_from_stem(stem)
  return asciimath if asciimath

  text = SafeAttr.read(stem, :text)
  return text.to_s if text.is_a?(String) && !text.strip.empty?

  ""
end