katex parse text

katexparse.js

			(function () {
				var replacements = {
					"α": "\\alpha",
					"β": "\\beta",
					"γ": "\\gamma",
					"δ": "\\delta",
					"ε": "\\epsilon",
					"ζ": "\\zeta",
					"η": "\\eta",
					"θ": "\\theta",
					"ι": "\\iota",
					"κ": "\\kappa",
					"λ": "\\lamda",
					"μ": "\\mi",
					"ν": "\\ni",
					"ξ": "\\xe",
					"ο": "\\omikron",
					"π": "\\pi",
					"ρ": "\\rho",
					"σ": "\\sigma",
					"τ": "\\taf",
					"υ": "\\ypsilon",
					"φ": "\\fi",
					"χ": "\\chi",
					"ψ": "\\psi",
					"ω": "\\omega",

				};
				var TEXT_NODE = document.TEXT_NODE;
				var ELEMENT_NODE = document.ELEMENT_NODE;
				var walk = function (node, delimiter) {
					var i, frag;
					switch (node.nodeType) {
						case ELEMENT_NODE:
							if (node.tagName.toLowerCase() === "script") return;
							for (i = node.childNodes.length - 1; i >= 0; i--) {
								walk(node.childNodes[i], delimiter);
							}
							break;
						case TEXT_NODE:
							if (node.textContent.indexOf(delimiter) < 0) return;
							frag = document.createElement("span");
							node.textContent.split(delimiter).forEach(function(part, i) {
								if (0 === i % 2) {
									frag.appendChild(document.createTextNode(part));
								}
								txt = part.replace(/[αβξδεζηθικλμνξοπρστυφχψω]/g, function(m) {
									return replacements[m];
								});
								var span = document.createElement("span");
								try {
									katex.render(txt, span);
								}
								catch (error) {
									console.error(error.message);
									span.textContent = part;
								}
								frag.appendChild(span);
							});
							node.parentNode.replaceChild(frag, node);
							break;
						default:
							return;

					}
				}
				// walk(document.body, "~~~");
				// walk(document.body, "~");
			})()