Add Turing lexer

Turing source files usually end with .t, but that clashes with Perl.

lexers/t/turing.go

@@ -0,0 +1,43 @@
+package t
+
+import (
+	. "github.com/alecthomas/chroma" // nolint
+	"github.com/alecthomas/chroma/lexers/internal"
+)
+
+// Turing lexer.
+var Turing = internal.Register(MustNewLexer(
+	&Config{
+		Name:      "Turing",
+		Aliases:   []string{"turing"},
+		Filenames: []string{"*.turing", "*.tu"},
+		MimeTypes: []string{"text/x-turing"},
+	},
+	Rules{
+		"root": {
+			{`\n`, Text, nil},
+			{`\s+`, Text, nil},
+			{`\\\n`, Text, nil},
+			{`%(.*?)\n`, CommentSingle, nil},
+			{`/(\\\n)?[*](.|\n)*?[*](\\\n)?/`, CommentMultiline, nil},
+			{`(var|fcn|function|proc|procedure|process|class|end|record|type|begin|case|loop|for|const|union|monitor|module|handler)\b`, KeywordDeclaration, nil},
+			{`(all|asm|assert|bind|bits|body|break|by|cheat|checked|close|condition|decreasing|def|deferred|else|elsif|exit|export|external|flexible|fork|forward|free|get|if|implement|import|include|inherit|init|invariant|label|new|objectclass|of|opaque|open|packed|pause|pervasive|post|pre|priority|put|quit|read|register|result|seek|self|set|signal|skip|tag|tell|then|timeout|to|unchecked|unqualified|wait|when|write)\b`, Keyword, nil},
+			{`(true|false)\b`, KeywordConstant, nil},
+			{Words(``, `\b`, `addressint`, `array`, `boolean`, `char`, `int`, `int1`, `int2`, `int4`, `int8`, `nat`, `nat1`, `nat2`, `nat4`, `nat8`, `pointer`, `real`, `real4`, `real8`, `string`, `enum`), KeywordType, nil},
+			{`\d+i`, LiteralNumber, nil},
+			{`\d+\.\d*([Ee][-+]\d+)?i`, LiteralNumber, nil},
+			{`\.\d+([Ee][-+]\d+)?i`, LiteralNumber, nil},
+			{`\d+[Ee][-+]\d+i`, LiteralNumber, nil},
+			{`\d+(\.\d+[eE][+\-]?\d+|\.\d*|[eE][+\-]?\d+)`, LiteralNumberFloat, nil},
+			{`\.\d+([eE][+\-]?\d+)?`, LiteralNumberFloat, nil},
+			{`0[0-7]+`, LiteralNumberOct, nil},
+			{`0[xX][0-9a-fA-F]+`, LiteralNumberHex, nil},
+			{`(0|[1-9][0-9]*)`, LiteralNumberInteger, nil},
+			{`(div|mod|rem|\*\*|=|<|>|>=|<=|not=|not|and|or|xor|=>|in|shl|shr|->|~|~=|~in|&|:=|\.\.|[\^+\-*/&#])`, Operator, nil},
+			{`'(\\['"\\abfnrtv]|\\x[0-9a-fA-F]{2}|\\[0-7]{1,3}|\\u[0-9a-fA-F]{4}|\\U[0-9a-fA-F]{8}|[^\\])'`, LiteralStringChar, nil},
+			{`"(\\\\|\\"|[^"])*"`, LiteralString, nil},
+			{`[()\[\]{}.,:]`, Punctuation, nil},
+			{`[^\W\d]\w*`, NameOther, nil},
+		},
+	},
+))