Added support for Dhall (#2473)

components.json

@@ -275,6 +275,10 @@
 			"title": "DAX",
 			"owner": "peterbud"
 		},
+		"dhall": {
+			"title": "Dhall",
+			"owner": "RunDevelopment"
+		},
 		"diff": {
 			"title": "Diff",
 			"owner": "uranusjr"

components/prism-dhall.js

@@ -0,0 +1,69 @@
+// ABNF grammar:
+// https://github.com/dhall-lang/dhall-lang/blob/master/standard/dhall.abnf
+
+Prism.languages.dhall = {
+	// Multi-line comments can be nested. E.g. {- foo {- bar -} -}
+	// The multi-line pattern is essentially this:
+	//   \{-(?:[^-{]|-(?!\})|\{(?!-)|<SELF>)*-\}
+	'comment': /--.*|\{-(?:[^-{]|-(?!\})|\{(?!-)|\{-(?:[^-{]|-(?!\})|\{(?!-))*-\})*-\}/,
+	'string': {
+		pattern: /"(?:[^"\\]|\\.)*"|''(?:[^']|'(?!')|'''|''\$\{)*''(?!'|\$)/,
+		greedy: true,
+		inside: {
+			'interpolation': {
+				pattern: /\$\{[^{}]*\}/,
+				inside: {
+					'expression': {
+						pattern: /(^\$\{)[\s\S]+(?=\}$)/,
+						lookbehind: true,
+						alias: 'language-dhall',
+						inside: null // see blow
+					},
+					'punctuation': /\$\{|\}/
+				}
+			}
+		}
+	},
+	'label': {
+		pattern: /`[^`]*`/,
+		greedy: true
+	},
+	'url': {
+		// https://github.com/dhall-lang/dhall-lang/blob/5fde8ef1bead6fb4e999d3c1ffe7044cd019d63a/standard/dhall.abnf#L596
+		pattern: /\bhttps?:\/\/[\w.:%!$&'*+;=@~-]+(?:\/[\w.:%!$&'*+;=@~-]*)*(?:\?[/?\w.:%!$&'*+;=@~-]*)?/,
+		greedy: true
+	},
+	'env': {
+		// https://github.com/dhall-lang/dhall-lang/blob/5fde8ef1bead6fb4e999d3c1ffe7044cd019d63a/standard/dhall.abnf#L661
+		pattern: /\benv:(?:(?!\d)\w+|"(?:[^"\\=]|\\.)*")/,
+		greedy: true,
+		inside: {
+			'function': /^env/,
+			'operator': /^:/,
+			'variable': /[\s\S]+/
+		}
+	},
+	'hash': {
+		// https://github.com/dhall-lang/dhall-lang/blob/5fde8ef1bead6fb4e999d3c1ffe7044cd019d63a/standard/dhall.abnf#L725
+		pattern: /\bsha256:[\da-fA-F]{64}\b/,
+		inside: {
+			'function': /sha256/,
+			'operator': /:/,
+			'number': /[\da-fA-F]{64}/
+		}
+	},
+
+	// https://github.com/dhall-lang/dhall-lang/blob/5fde8ef1bead6fb4e999d3c1ffe7044cd019d63a/standard/dhall.abnf#L359
+	'keyword': /\b(?:as|assert|else|forall|if|in|let|merge|missing|then|toMap|using|with)\b|\u2200/,
+	'builtin': /\b(?:Some|None)\b/,
+
+	'boolean': /\b(?:False|True)\b/,
+	'number': /\bNaN\b|-?\bInfinity\b|[+-]?\b(?:0x[\da-fA-F]+|\d+(?:\.\d+)?(?:e[+-]?\d+)?)\b/,
+	'operator': /\/\\|\/\/\\\\|&&|\|\||[!=]=|===|\/\/|->|\+\+|::|[+*#@=:?<>|\\\u2227\u2a53\u2261\u2afd\u03bb\u2192]/,
+	'punctuation': /\.\.|[{}\[\](),./]/,
+
+	// we'll just assume that every capital word left is a type name
+	'class-name': /\b[A-Z]\w*\b/
+};
+
+Prism.languages.dhall.string.inside.interpolation.inside.expression.inside = Prism.languages.dhall;

examples/prism-dhall.html

@@ -0,0 +1,30 @@
+<h2>Full example</h2>
+<pre><code>
+-- source: https://github.com/dhall-lang/dhall-lang/blob/master/Prelude/Optional/head.dhall
+
+{-
+Returns the first non-empty `Optional` value in a `List`
+-}
+let head
+    : ∀(a : Type) → List (Optional a) → Optional a
+    = λ(a : Type) →
+      λ(xs : List (Optional a)) →
+        List/fold
+          (Optional a)
+          xs
+          (Optional a)
+          ( λ(l : Optional a) →
+            λ(r : Optional a) →
+              merge { Some = λ(x : a) → Some x, None = r } l
+          )
+          (None a)
+
+let example0 = assert : head Natural [ None Natural, Some 1, Some 2 ] ≡ Some 1
+
+let example1 =
+      assert : head Natural [ None Natural, None Natural ] ≡ None Natural
+
+let example2 =
+      assert : head Natural ([] : List (Optional Natural)) ≡ None Natural
+
+in  head</code></pre>

tests/languages/dhall/boolean_feature.test

@@ -0,0 +1,13 @@
+False
+True
+
+----------------------------------------------------
+
+[
+	["boolean", "False"],
+	["boolean", "True"]
+]
+
+----------------------------------------------------
+
+Checks for Bool literals.

tests/languages/dhall/comment_feature.test

@@ -0,0 +1,20 @@
+-- comment
+
+{-
+	comment
+	{-
+		nested comment
+	-}
+-}
+
+----------------------------------------------------
+
+[
+	["comment", "-- comment"],
+
+	["comment", "{-\n\tcomment\n\t{-\n\t\tnested comment\n\t-}\n-}"]
+]
+
+----------------------------------------------------
+
+Checks for comments.

tests/languages/dhall/env_feature.test

@@ -0,0 +1,21 @@
+env:DHALL_PRELUDE
+env:"Quotes variable"
+
+----------------------------------------------------
+
+[
+	["env", [
+		["function", "env"],
+		["operator", ":"],
+		["variable", "DHALL_PRELUDE"]
+	]],
+	["env", [
+		["function", "env"],
+		["operator", ":"],
+		["variable", "\"Quotes variable\""]
+	]]
+]
+
+----------------------------------------------------
+
+Checks for environment variables.

tests/languages/dhall/hash_feature.test

@@ -0,0 +1,15 @@
+sha256:33f7f4c3aff62e5ecf4848f964363133452d420dcde045784518fb59fa970037
+
+----------------------------------------------------
+
+[
+	["hash", [
+		["function", "sha256"],
+		["operator", ":"],
+		["number", "33f7f4c3aff62e5ecf4848f964363133452d420dcde045784518fb59fa970037"]
+	]]
+]
+
+----------------------------------------------------
+
+Checks for sha256 hashes.

tests/languages/dhall/keyword_feature.test

@@ -0,0 +1,39 @@
+as
+assert
+else
+forall
+if
+in
+let
+merge
+missing
+then
+toMap
+using
+with
+
+∀
+
+----------------------------------------------------
+
+[
+	["keyword", "as"],
+	["keyword", "assert"],
+	["keyword", "else"],
+	["keyword", "forall"],
+	["keyword", "if"],
+	["keyword", "in"],
+	["keyword", "let"],
+	["keyword", "merge"],
+	["keyword", "missing"],
+	["keyword", "then"],
+	["keyword", "toMap"],
+	["keyword", "using"],
+	["keyword", "with"],
+
+	["keyword", "∀"]
+]
+
+----------------------------------------------------
+
+Checks for keywords.

tests/languages/dhall/label_feature.test

@@ -0,0 +1,11 @@
+`"foo"'s 123`
+
+----------------------------------------------------
+
+[
+	["label", "`\"foo\"'s 123`"]
+]
+
+----------------------------------------------------
+
+Checks for escaped labels.

tests/languages/dhall/number_feature.test

@@ -0,0 +1,35 @@
+0
+123
+123e-5
+-123e+2
+123.456
++123.456e-7
+0xFF
+-0xFF
++0xFF
+
+Infinity
+-Infinity
+NaN
+
+----------------------------------------------------
+
+[
+	["number", "0"],
+	["number", "123"],
+	["number", "123e-5"],
+	["number", "-123e+2"],
+	["number", "123.456"],
+	["number", "+123.456e-7"],
+	["number", "0xFF"],
+	["number", "-0xFF"],
+	["number", "+0xFF"],
+
+	["number", "Infinity"],
+	["number", "-Infinity"],
+	["number", "NaN"]
+]
+
+----------------------------------------------------
+
+Checks for numeric literals.

tests/languages/dhall/operator_feature.test

@@ -0,0 +1,44 @@
+/\ //\\ && || != == == // -> ++ ::
+
++ * # | = : ? < > | \
+
+∧ ⩓ ≡ ⫽ λ →
+
+----------------------------------------------------
+
+[
+	["operator", "/\\"],
+	["operator", "//\\\\"],
+	["operator", "&&"],
+	["operator", "||"],
+	["operator", "!="],
+	["operator", "=="],
+	["operator", "=="],
+	["operator", "//"],
+	["operator", "->"],
+	["operator", "++"],
+	["operator", "::"],
+
+	["operator", "+"],
+	["operator", "*"],
+	["operator", "#"],
+	["operator", "|"],
+	["operator", "="],
+	["operator", ":"],
+	["operator", "?"],
+	["operator", "<"],
+	["operator", ">"],
+	["operator", "|"],
+	["operator", "\\"],
+
+	["operator", "∧"],
+	["operator", "⩓"],
+	["operator", "≡"],
+	["operator", "⫽"],
+	["operator", "λ"],
+	["operator", "→"]
+]
+
+----------------------------------------------------
+
+Checks for operators.

tests/languages/dhall/punctuation_feature.test

@@ -0,0 +1,23 @@
+. .. /
+
+{ } [ ] ( ) ,
+
+----------------------------------------------------
+
+[
+	["punctuation", "."],
+	["punctuation", ".."],
+	["punctuation", "/"],
+
+	["punctuation", "{"],
+	["punctuation", "}"],
+	["punctuation", "["],
+	["punctuation", "]"],
+	["punctuation", "("],
+	["punctuation", ")"],
+	["punctuation", ","]
+]
+
+----------------------------------------------------
+
+Checks for punctuation.