Pagination, readable error messages to user, syntax highlighting started.

Pagination now works. Temporary hardcoded 10 pastes per page, will be put
in configuration later. Maybe.

From now user will receive readable error message if error occured.

Started to work on syntax highlighting, tried to make lexers detection
work but apparently to no avail.

vendor/github.com/alecthomas/chroma/lexers/o/objectivec.go

@@ -0,0 +1,165 @@
+package o
+
+import (
+	. "github.com/alecthomas/chroma" // nolint
+	"github.com/alecthomas/chroma/lexers/internal"
+)
+
+// Objective-C lexer.
+var ObjectiveC = internal.Register(MustNewLexer(
+	&Config{
+		Name:      "Objective-C",
+		Aliases:   []string{"objective-c", "objectivec", "obj-c", "objc"},
+		Filenames: []string{"*.m", "*.h"},
+		MimeTypes: []string{"text/x-objective-c"},
+	},
+	Rules{
+		"statements": {
+			{`@"`, LiteralString, Push("string")},
+			{`@(YES|NO)`, LiteralNumber, nil},
+			{`@'(\\.|\\[0-7]{1,3}|\\x[a-fA-F0-9]{1,2}|[^\\\'\n])'`, LiteralStringChar, nil},
+			{`@(\d+\.\d*|\.\d+|\d+)[eE][+-]?\d+[lL]?`, LiteralNumberFloat, nil},
+			{`@(\d+\.\d*|\.\d+|\d+[fF])[fF]?`, LiteralNumberFloat, nil},
+			{`@0x[0-9a-fA-F]+[Ll]?`, LiteralNumberHex, nil},
+			{`@0[0-7]+[Ll]?`, LiteralNumberOct, nil},
+			{`@\d+[Ll]?`, LiteralNumberInteger, nil},
+			{`@\(`, Literal, Push("literal_number")},
+			{`@\[`, Literal, Push("literal_array")},
+			{`@\{`, Literal, Push("literal_dictionary")},
+			{Words(``, `\b`, `@selector`, `@private`, `@protected`, `@public`, `@encode`, `@synchronized`, `@try`, `@throw`, `@catch`, `@finally`, `@end`, `@property`, `@synthesize`, `__bridge`, `__bridge_transfer`, `__autoreleasing`, `__block`, `__weak`, `__strong`, `weak`, `strong`, `copy`, `retain`, `assign`, `unsafe_unretained`, `atomic`, `nonatomic`, `readonly`, `readwrite`, `setter`, `getter`, `typeof`, `in`, `out`, `inout`, `release`, `class`, `@dynamic`, `@optional`, `@required`, `@autoreleasepool`), Keyword, nil},
+			{Words(``, `\b`, `id`, `instancetype`, `Class`, `IMP`, `SEL`, `BOOL`, `IBOutlet`, `IBAction`, `unichar`), KeywordType, nil},
+			{`@(true|false|YES|NO)\n`, NameBuiltin, nil},
+			{`(YES|NO|nil|self|super)\b`, NameBuiltin, nil},
+			{`(Boolean|UInt8|SInt8|UInt16|SInt16|UInt32|SInt32)\b`, KeywordType, nil},
+			{`(TRUE|FALSE)\b`, NameBuiltin, nil},
+			{`(@interface|@implementation)(\s+)`, ByGroups(Keyword, Text), Push("#pop", "oc_classname")},
+			{`(@class|@protocol)(\s+)`, ByGroups(Keyword, Text), Push("#pop", "oc_forward_classname")},
+			{`@`, Punctuation, nil},
+			{`(L?)(")`, ByGroups(LiteralStringAffix, LiteralString), Push("string")},
+			{`(L?)(')(\\.|\\[0-7]{1,3}|\\x[a-fA-F0-9]{1,2}|[^\\\'\n])(')`, ByGroups(LiteralStringAffix, LiteralStringChar, LiteralStringChar, LiteralStringChar), nil},
+			{`(\d+\.\d*|\.\d+|\d+)[eE][+-]?\d+[LlUu]*`, LiteralNumberFloat, nil},
+			{`(\d+\.\d*|\.\d+|\d+[fF])[fF]?`, LiteralNumberFloat, nil},
+			{`0x[0-9a-fA-F]+[LlUu]*`, LiteralNumberHex, nil},
+			{`0[0-7]+[LlUu]*`, LiteralNumberOct, nil},
+			{`\d+[LlUu]*`, LiteralNumberInteger, nil},
+			{`\*/`, Error, nil},
+			{`[~!%^&*+=|?:<>/-]`, Operator, nil},
+			{`[()\[\],.]`, Punctuation, nil},
+			{Words(``, `\b`, `asm`, `auto`, `break`, `case`, `const`, `continue`, `default`, `do`, `else`, `enum`, `extern`, `for`, `goto`, `if`, `register`, `restricted`, `return`, `sizeof`, `static`, `struct`, `switch`, `typedef`, `union`, `volatile`, `while`), Keyword, nil},
+			{`(bool|int|long|float|short|double|char|unsigned|signed|void)\b`, KeywordType, nil},
+			{Words(``, `\b`, `inline`, `_inline`, `__inline`, `naked`, `restrict`, `thread`, `typename`), KeywordReserved, nil},
+			{`(__m(128i|128d|128|64))\b`, KeywordReserved, nil},
+			{Words(`__`, `\b`, `asm`, `int8`, `based`, `except`, `int16`, `stdcall`, `cdecl`, `fastcall`, `int32`, `declspec`, `finally`, `int64`, `try`, `leave`, `wchar_t`, `w64`, `unaligned`, `raise`, `noop`, `identifier`, `forceinline`, `assume`), KeywordReserved, nil},
+			{`(true|false|NULL)\b`, NameBuiltin, nil},
+			{`([a-zA-Z_]\w*)(\s*)(:)(?!:)`, ByGroups(NameLabel, Text, Punctuation), nil},
+			{`[a-zA-Z_]\w*`, Name, nil},
+		},
+		"oc_classname": {
+			{`([a-zA-Z$_][\w$]*)(\s*:\s*)([a-zA-Z$_][\w$]*)?(\s*)(\{)`, ByGroups(NameClass, Text, NameClass, Text, Punctuation), Push("#pop", "oc_ivars")},
+			{`([a-zA-Z$_][\w$]*)(\s*:\s*)([a-zA-Z$_][\w$]*)?`, ByGroups(NameClass, Text, NameClass), Pop(1)},
+			{`([a-zA-Z$_][\w$]*)(\s*)(\([a-zA-Z$_][\w$]*\))(\s*)(\{)`, ByGroups(NameClass, Text, NameLabel, Text, Punctuation), Push("#pop", "oc_ivars")},
+			{`([a-zA-Z$_][\w$]*)(\s*)(\([a-zA-Z$_][\w$]*\))`, ByGroups(NameClass, Text, NameLabel), Pop(1)},
+			{`([a-zA-Z$_][\w$]*)(\s*)(\{)`, ByGroups(NameClass, Text, Punctuation), Push("#pop", "oc_ivars")},
+			{`([a-zA-Z$_][\w$]*)`, NameClass, Pop(1)},
+		},
+		"oc_forward_classname": {
+			{`([a-zA-Z$_][\w$]*)(\s*,\s*)`, ByGroups(NameClass, Text), Push("oc_forward_classname")},
+			{`([a-zA-Z$_][\w$]*)(\s*;?)`, ByGroups(NameClass, Text), Pop(1)},
+		},
+		"oc_ivars": {
+			Include("whitespace"),
+			Include("statements"),
+			{`;`, Punctuation, nil},
+			{`\{`, Punctuation, Push()},
+			{`\}`, Punctuation, Pop(1)},
+		},
+		"root": {
+			{`^([-+])(\s*)(\(.*?\))?(\s*)([a-zA-Z$_][\w$]*:?)`, ByGroups(Punctuation, Text, UsingSelf("root"), Text, NameFunction), Push("method")},
+			Include("whitespace"),
+			{`((?:[\w*\s])+?(?:\s|[*]))([a-zA-Z_]\w*)(\s*\([^;]*?\))([^;{]*)(\{)`, ByGroups(UsingSelf("root"), NameFunction, UsingSelf("root"), UsingSelf("root"), Punctuation), Push("function")},
+			{`((?:[\w*\s])+?(?:\s|[*]))([a-zA-Z_]\w*)(\s*\([^;]*?\))([^;]*)(;)`, ByGroups(UsingSelf("root"), NameFunction, UsingSelf("root"), UsingSelf("root"), Punctuation), nil},
+			Default(Push("statement")),
+		},
+		"method": {
+			Include("whitespace"),
+			{`,`, Punctuation, nil},
+			{`\.\.\.`, Punctuation, nil},
+			{`(\(.*?\))(\s*)([a-zA-Z$_][\w$]*)`, ByGroups(UsingSelf("root"), Text, NameVariable), nil},
+			{`[a-zA-Z$_][\w$]*:`, NameFunction, nil},
+			{`;`, Punctuation, Pop(1)},
+			{`\{`, Punctuation, Push("function")},
+			Default(Pop(1)),
+		},
+		"literal_number": {
+			{`\(`, Punctuation, Push("literal_number_inner")},
+			{`\)`, Literal, Pop(1)},
+			Include("statement"),
+		},
+		"literal_number_inner": {
+			{`\(`, Punctuation, Push()},
+			{`\)`, Punctuation, Pop(1)},
+			Include("statement"),
+		},
+		"literal_array": {
+			{`\[`, Punctuation, Push("literal_array_inner")},
+			{`\]`, Literal, Pop(1)},
+			Include("statement"),
+		},
+		"literal_array_inner": {
+			{`\[`, Punctuation, Push()},
+			{`\]`, Punctuation, Pop(1)},
+			Include("statement"),
+		},
+		"literal_dictionary": {
+			{`\}`, Literal, Pop(1)},
+			Include("statement"),
+		},
+		"whitespace": {
+			{`^#if\s+0`, CommentPreproc, Push("if0")},
+			{`^#`, CommentPreproc, Push("macro")},
+			{`^(\s*(?:/[*].*?[*]/\s*)?)(#if\s+0)`, ByGroups(UsingSelf("root"), CommentPreproc), Push("if0")},
+			{`^(\s*(?:/[*].*?[*]/\s*)?)(#)`, ByGroups(UsingSelf("root"), CommentPreproc), Push("macro")},
+			{`\n`, Text, nil},
+			{`\s+`, Text, nil},
+			{`\\\n`, Text, nil},
+			{`//(\n|[\w\W]*?[^\\]\n)`, CommentSingle, nil},
+			{`/(\\\n)?[*][\w\W]*?[*](\\\n)?/`, CommentMultiline, nil},
+			{`/(\\\n)?[*][\w\W]*`, CommentMultiline, nil},
+		},
+		"statement": {
+			Include("whitespace"),
+			Include("statements"),
+			{`[{}]`, Punctuation, nil},
+			{`;`, Punctuation, Pop(1)},
+		},
+		"function": {
+			Include("whitespace"),
+			Include("statements"),
+			{`;`, Punctuation, nil},
+			{`\{`, Punctuation, Push()},
+			{`\}`, Punctuation, Pop(1)},
+		},
+		"string": {
+			{`"`, LiteralString, Pop(1)},
+			{`\\([\\abfnrtv"\']|x[a-fA-F0-9]{2,4}|u[a-fA-F0-9]{4}|U[a-fA-F0-9]{8}|[0-7]{1,3})`, LiteralStringEscape, nil},
+			{`[^\\"\n]+`, LiteralString, nil},
+			{`\\\n`, LiteralString, nil},
+			{`\\`, LiteralString, nil},
+		},
+		"macro": {
+			{`(include)(\s*(?:/[*].*?[*]/\s*)?)([^\n]+)`, ByGroups(CommentPreproc, Text, CommentPreprocFile), nil},
+			{`[^/\n]+`, CommentPreproc, nil},
+			{`/[*](.|\n)*?[*]/`, CommentMultiline, nil},
+			{`//.*?\n`, CommentSingle, Pop(1)},
+			{`/`, CommentPreproc, nil},
+			{`(?<=\\)\n`, CommentPreproc, nil},
+			{`\n`, CommentPreproc, Pop(1)},
+		},
+		"if0": {
+			{`^\s*#if.*?(?<!\\)\n`, CommentPreproc, Push()},
+			{`^\s*#el(?:se|if).*\n`, CommentPreproc, Pop(1)},
+			{`^\s*#endif.*?(?<!\\)\n`, CommentPreproc, Pop(1)},
+			{`.*?\n`, Comment, nil},
+		},
+	},
+))

vendor/github.com/alecthomas/chroma/lexers/o/ocaml.go

@@ -0,0 +1,66 @@
+package o
+
+import (
+	. "github.com/alecthomas/chroma" // nolint
+	"github.com/alecthomas/chroma/lexers/internal"
+)
+
+// Ocaml lexer.
+var Ocaml = internal.Register(MustNewLexer(
+	&Config{
+		Name:      "OCaml",
+		Aliases:   []string{"ocaml"},
+		Filenames: []string{"*.ml", "*.mli", "*.mll", "*.mly"},
+		MimeTypes: []string{"text/x-ocaml"},
+	},
+	Rules{
+		"escape-sequence": {
+			{`\\[\\"\'ntbr]`, LiteralStringEscape, nil},
+			{`\\[0-9]{3}`, LiteralStringEscape, nil},
+			{`\\x[0-9a-fA-F]{2}`, LiteralStringEscape, nil},
+		},
+		"root": {
+			{`\s+`, Text, nil},
+			{`false|true|\(\)|\[\]`, NameBuiltinPseudo, nil},
+			{`\b([A-Z][\w\']*)(?=\s*\.)`, NameNamespace, Push("dotted")},
+			{`\b([A-Z][\w\']*)`, NameClass, nil},
+			{`\(\*(?![)])`, Comment, Push("comment")},
+			{`\b(as|assert|begin|class|constraint|do|done|downto|else|end|exception|external|false|for|fun|function|functor|if|in|include|inherit|initializer|lazy|let|match|method|module|mutable|new|object|of|open|private|raise|rec|sig|struct|then|to|true|try|type|value|val|virtual|when|while|with)\b`, Keyword, nil},
+			{"(~|\\}|\\|]|\\||\\{<|\\{|`|_|]|\\[\\||\\[>|\\[<|\\[|\\?\\?|\\?|>\\}|>]|>|=|<-|<|;;|;|:>|:=|::|:|\\.\\.|\\.|->|-\\.|-|,|\\+|\\*|\\)|\\(|&&|&|#|!=)", Operator, nil},
+			{`([=<>@^|&+\*/$%-]|[!?~])?[!$%&*+\./:<=>?@^|~-]`, Operator, nil},
+			{`\b(and|asr|land|lor|lsl|lxor|mod|or)\b`, OperatorWord, nil},
+			{`\b(unit|int|float|bool|string|char|list|array)\b`, KeywordType, nil},
+			{`[^\W\d][\w']*`, Name, nil},
+			{`-?\d[\d_]*(.[\d_]*)?([eE][+\-]?\d[\d_]*)`, LiteralNumberFloat, nil},
+			{`0[xX][\da-fA-F][\da-fA-F_]*`, LiteralNumberHex, nil},
+			{`0[oO][0-7][0-7_]*`, LiteralNumberOct, nil},
+			{`0[bB][01][01_]*`, LiteralNumberBin, nil},
+			{`\d[\d_]*`, LiteralNumberInteger, nil},
+			{`'(?:(\\[\\\"'ntbr ])|(\\[0-9]{3})|(\\x[0-9a-fA-F]{2}))'`, LiteralStringChar, nil},
+			{`'.'`, LiteralStringChar, nil},
+			{`'`, Keyword, nil},
+			{`"`, LiteralStringDouble, Push("string")},
+			{`[~?][a-z][\w\']*:`, NameVariable, nil},
+		},
+		"comment": {
+			{`[^(*)]+`, Comment, nil},
+			{`\(\*`, Comment, Push()},
+			{`\*\)`, Comment, Pop(1)},
+			{`[(*)]`, Comment, nil},
+		},
+		"string": {
+			{`[^\\"]+`, LiteralStringDouble, nil},
+			Include("escape-sequence"),
+			{`\\\n`, LiteralStringDouble, nil},
+			{`"`, LiteralStringDouble, Pop(1)},
+		},
+		"dotted": {
+			{`\s+`, Text, nil},
+			{`\.`, Punctuation, nil},
+			{`[A-Z][\w\']*(?=\s*\.)`, NameNamespace, nil},
+			{`[A-Z][\w\']*`, NameClass, Pop(1)},
+			{`[a-z_][\w\']*`, Name, Pop(1)},
+			Default(Pop(1)),
+		},
+	},
+))