Add ToMathML trait and implementation for greek letters

src/format/mathml.rs

@@ -0,0 +1,50 @@
+use crate::tokens::Greek;
+
+pub trait ToMathML {
+    fn to_mathml(&self) -> String;
+}
+
+impl ToMathML for Greek {
+    fn to_mathml(&self) -> String {
+        let inner = match self {
+            Greek::Alpha => "α",
+            Greek::Beta => "β",
+            Greek::Gamma => "γ",
+            Greek::BigGamma => "Γ",
+            Greek::Delta => "δ",
+            Greek::BigDelta => "Δ",
+            Greek::Epsilon => "ε",
+            Greek::VarEpsilon => "ε",
+            Greek::Zeta => "ζ",
+            Greek::Eta => "η",
+            Greek::Theta => "θ",
+            Greek::BigTheta => "Θ",
+            Greek::VarTheta => "θ",
+            Greek::Iota => "ι",
+            Greek::Kappa => "κ",
+            Greek::Lambda => "λ",
+            Greek::BigLambda => "Λ",
+            Greek::Mu => "μ",
+            Greek::Nu => "ν",
+            Greek::Xi => "ξ",
+            Greek::BigXi => "Ξ",
+            Greek::Pi => "π",
+            Greek::BigPi => "Π",
+            Greek::Rho => "ρ",
+            Greek::Sigma => "σ",
+            Greek::BigSigma => "Σ",
+            Greek::Tau => "τ",
+            Greek::Upsilon => "υ",
+            Greek::Phi => "φ",
+            Greek::BigPhi => "Φ",
+            Greek::VarPhi => "φ",
+            Greek::Chi => "χ",
+            Greek::Psi => "ψ",
+            Greek::BigPsi => "Ψ",
+            Greek::Omega => "ω",
+            Greek::BigOmega => "Ω",
+        };
+
+        format!("<mi>{}</mi>", inner)
+    }
+}

src/format/mod.rs

@@ -0,0 +1 @@
+pub mod mathml;

src/lib.rs

@@ -12,6 +12,7 @@ use crate::parsing::tokenizer::Tokenizer;
 use crate::parsing::tree_parser::TreeParser;
 
 pub mod elements;
+pub mod format;
 pub mod parsing;
 pub mod tokens;
 pub(crate) mod utils;