Module: AsciiChem::Greek

Defined in:
lib/asciichem/greek.rb

Overview

AsciiMath-style Greek word → Unicode symbol table. Used by the grammar and transform to accept typed Greek words (alpha, Delta, etc.) alongside Unicode characters (α, Δ).

Single source of truth — the stereo grammar, the conditions translator, and any future site that needs Greek letters all read from this hash. Adding a new word is one entry here, not edits scattered across the grammar.

Constant Summary collapse

LOWERCASE = 
{
  "alpha"   => "α",
  "beta"    => "β",
  "gamma"   => "γ",
  "delta"   => "δ",
  "epsilon" => "ε",
  "zeta"    => "ζ",
  "eta"     => "η",
  "theta"   => "θ",
  "iota"    => "ι",
  "kappa"   => "κ",
  "lambda"  => "λ",
  "mu"      => "μ",
  "nu"      => "ν",
  "xi"      => "ξ",
  "omicron" => "ο",
  "pi"      => "π",
  "rho"     => "ρ",
  "sigma"   => "σ",
  "tau"     => "τ",
  "upsilon" => "υ",
  "phi"     => "φ",
  "chi"     => "χ",
  "psi"     => "ψ",
  "omega"   => "ω"
}.freeze
UPPERCASE = 
{
  "Alpha"   => "Α",
  "Beta"    => "Β",
  "Gamma"   => "Γ",
  "Delta"   => "Δ",
  "Epsilon" => "Ε",
  "Zeta"    => "Ζ",
  "Eta"     => "Η",
  "Theta"   => "Θ",
  "Iota"    => "Ι",
  "Kappa"   => "Κ",
  "Lambda"  => "Λ",
  "Mu"      => "Μ",
  "Nu"      => "Ν",
  "Xi"      => "Ξ",
  "Omicron" => "Ο",
  "Pi"      => "Π",
  "Rho"     => "Ρ",
  "Sigma"   => "Σ",
  "Tau"     => "Τ",
  "Upsilon" => "Υ",
  "Phi"     => "Φ",
  "Chi"     => "Χ",
  "Psi"     => "Ψ",
  "Omega"   => "Ω"
}.freeze
ALL = 
LOWERCASE.merge(UPPERCASE).freeze

Class Method Summary collapse

Class Method Details

.translate(text) ⇒ Object

Translate every Greek word in text to its Unicode symbol. Non-word substrings pass through unchanged. Longest-word-first so "eta" doesn't shadow "beta" (which contains "eta" as a suffix).



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# File 'lib/asciichem/greek.rb', line 72

def self.translate(text)
  return text if text.nil? || text.empty?

  sorted_words = ALL.keys.sort_by(&:length).reverse
  pattern = /#{sorted_words.map { |w| Regexp.escape(w) }.join("|")}/
  text.gsub(pattern) { |match| ALL.fetch(match) }
end