Added support for OpenQasm (#2797)

components.json

@@ -850,6 +850,11 @@
 			],
 			"owner": "Milania1"
 		},
+		"openqasm": {
+			"title": "OpenQasm",
+			"alias": "qasm",
+			"owner": "RunDevelopment"
+		},
 		"oz": {
 			"title": "Oz",
 			"owner": "Golmote"

components/prism-openqasm.js

@@ -0,0 +1,23 @@
+// https://qiskit.github.io/openqasm/grammar/index.html
+
+Prism.languages.openqasm = {
+	'comment': /\/\*[\s\S]*?\*\/|\/\/.*/,
+	'string': {
+		pattern: /"[^"\r\n\t]*"|'[^'\r\n\t]*'/,
+		greedy: true
+	},
+
+	'keyword': /\b(?:barrier|boxas|boxto|break|const|continue|ctrl|def|defcal|defcalgrammar|delay|else|end|for|gate|gphase|if|in|include|inv|kernel|lengthof|let|measure|pow|reset|return|rotary|stretchinf|while|CX|OPENQASM|U)\b|#pragma\b/,
+	'class-name': /\b(?:angle|bit|bool|creg|fixed|float|int|length|qreg|qubit|stretch|uint)\b/,
+	'function': /\b(?:sin|cos|tan|exp|ln|sqrt|rotl|rotr|popcount)\b(?=\s*\()/,
+
+	'constant': /\b(?:pi|tau|euler)\b|[π𝜏ℇ]/,
+	'number': {
+		pattern: /(^|[^.\w$])(?:\d+(?:\.\d*)?|\.\d+)(?:e[+-]?\d+)?(?:dt|ns|us|µs|ms|s)?/i,
+		lookbehind: true
+	},
+	'operator': /->|>>=?|<<=?|&&|\|\||\+\+|--|[!=<>&|~^+\-*/%]=?|@/,
+	'punctuation': /[(){}\[\];,:.]/
+};
+
+Prism.languages.qasm = Prism.languages.openqasm;

examples/prism-openqasm.html

@@ -0,0 +1,43 @@
+<h2>Full example</h2>
+<pre class="language-cpp"><code>// https://github.com/Qiskit/openqasm
+/*
+ * Repeat-until-success circuit for Rz(theta),
+ * cos(theta-pi)=3/5, from Nielsen and Chuang, Chapter 4.
+ */
+OPENQASM 3;
+include "stdgates.inc";
+
+/*
+ * Applies identity if out is 01, 10, or 11 and a Z-rotation by
+ * theta + pi where cos(theta)=3/5 if out is 00.
+ * The 00 outcome occurs with probability 5/8.
+ */
+def segment qubit[2]:anc, qubit:psi -> bit[2] {
+  bit[2] b;
+  reset anc;
+  h anc;
+  ccx anc[0], anc[1], psi;
+  s psi;
+  ccx anc[0], anc[1], psi;
+  z psi;
+  h anc;
+  measure anc -> b;
+  return b;
+}
+
+qubit input;
+qubit ancilla[2];
+bit flags[2] = "11";
+bit output;
+
+reset input;
+h input;
+
+// braces are optional in this case
+while(int(flags) != 0) {
+  flags = segment ancilla, input;
+}
+rz(pi - arccos(3 / 5)) input;
+h input;
+output = measure input;  // should get zero
+</code></pre>

plugins/autoloader/prism-autoloader.js

@@ -205,6 +205,7 @@
 		"n4jsd": "n4js",
 		"nani": "naniscript",
 		"objc": "objectivec",
+		"qasm": "openqasm",
 		"objectpascal": "pascal",
 		"px": "pcaxis",
 		"pcode": "peoplecode",

plugins/show-language/prism-show-language.js

@@ -147,6 +147,8 @@
 		"objc": "Objective-C",
 		"ocaml": "OCaml",
 		"opencl": "OpenCL",
+		"openqasm": "OpenQasm",
+		"qasm": "OpenQasm",
 		"parigp": "PARI/GP",
 		"objectpascal": "Object Pascal",
 		"psl": "PATROL Scripting Language",