Rebol [
Title: "Codec: HTML entities"
Name: html-entities
Type: module
Version: 1.1.0
Date: 21-Oct-2025
Options: [delay]
Purpose: "To decode HTML entities in a text"
File: https://raw.githubusercontent.com/Oldes/Rebol3/master/src/mezz/codec-html-entities.reb
Author: "Oldes"
Rights: http://opensource.org/licenses/Apache-2.0
Usage: [
"Test: ♠ & ¢ and Δδ ¾" =
decode 'html-entities {Test: ♠ & ¢ <a> and Δδ ¾}
]
TODO: {
*Encoder
}
]
html-entities: #[
;@@ https://eastmanreference.com/list-of-html-entity-names-and-numbers
;-- Punctuation, programming, and other common symbols
"lt" #"^(3C)" ; 60 Open tag
"gt" #"^(3E)" ; 62 Close tag
"quot" #"^(22)" ; 34 Double quote
"apos" #"^(27)" ; 39 Apostrophe / single quote
"amp" #"^(26)" ; 38 Ampersand
"nbsp" #"^(A0)" ; 160 Space (non-breaking)
"brvbar" #"^(A6)" ; 166 Broken bar
"iexcl" #"^(A1)" ; 161 Upside down exclamation mark
"iquest" #"^(BF)" ; 191 Upside down question mark
"sect" #"^(A7)" ; 167 Section symbol
"uml" #"^(A8)" ; 168 Umlaut
"ordf" #"^(AA)" ; 170 Feminine ordinal indicator
"ordm" #"^(BA)" ; 186 Masculine ordinal indicator
"laquo" #"^(AB)" ; 171 Open double angles
"raquo" #"^(BB)" ; 187 Close double angles
"not" #"^(AC)" ; 172 Not sign
"shy" #"^(AD)" ; 173 Soft hyphen
"macr" #"^(AF)" ; 175 Overline
"acute" #"^(B4)" ; 180 Acute accent
"para" #"^(B6)" ; 182 Pilcrow (paragraph)
"middot" #"^(B7)" ; 183 Georgian comma
"cedil" #"^(B8)" ; 184 Cedilla
;-- Math symbols
"minus" #"^(2212)" ; 8722 Minus sign (subtraction)
"times" #"^(D7)" ; 215 Multiplication sign
"divide" #"^(F7)" ; 247 Division sign
"plusmn" #"^(B1)" ; 177 Plus / minus
"le" #"^(2264)" ; 8804 Less or equal
"ge" #"^(2265)" ; 8805 Greater or equal
"sup1" #"^(B9)" ; 185 Superscript 1
"sup2" #"^(B2)" ; 178 Superscript 2
"sup3" #"^(B3)" ; 179 Superscript 3
"frac14" #"^(BC)" ; 188 1/4
"frac12" #"^(BD)" ; 189 1/2
"frac34" #"^(BE)" ; 190 3/4
"forall" #"^(2200)" ; 8704 For all
"part" #"^(2202)" ; 8706 Part
"exist" #"^(2203)" ; 8707 Exist
"empty" #"^(2205)" ; 8709 Empty
"nabla" #"^(2207)" ; 8711 Nabla
"isin" #"^(2208)" ; 8712 Is in
"notin" #"^(2209)" ; 8713 Not in
"ni" #"^(220B)" ; 8715 Ni
"prod" #"^(220F)" ; 8719 Product
"sum" #"^(2211)" ; 8721 Sum
"lowast" #"^(2217)" ; 8727 Asterisk (Lowast)
"radic" #"^(221A)" ; 8730 Square root
"prop" #"^(221D)" ; 8733 Proportional to
"infin" #"^(221E)" ; 8734 Infinity
"ang" #"^(2220)" ; 8736 Angle
"and" #"^(2227)" ; 8743 And
"or" #"^(2228)" ; 8744 Or
"cap" #"^(2229)" ; 8745 Cap
"cup" #"^(222A)" ; 8746 Cup
"int" #"^(222B)" ; 8747 Integral
"there4" #"^(2234)" ; 8756 Therefore
"sim" #"^(223C)" ; 8764 Similar to
"cong" #"^(2245)" ; 8773 Congurent to
"asymp" #"^(2248)" ; 8776 Almost equal
"ne" #"^(2260)" ; 8800 Not equal
"equiv" #"^(2261)" ; 8801 Equivalent
"sub" #"^(2282)" ; 8834 Subset of
"sup" #"^(2283)" ; 8835 Superset of
"nsub" #"^(2284)" ; 8836 Not subset of
"sube" #"^(2286)" ; 8838 Subset or equal
"supe" #"^(2287)" ; 8839 Superset or equal
"oplus" #"^(2295)" ; 8853 Circled plus
"otimes" #"^(2297)" ; 8855 Circled times
;-- Unit of measure symbols
"deg" #"^(B0)" ; 176 Degrees
"micro" #"^(B5)" ; 181 Micro
;-- Copyright, registered, trademark
"copy" #"^(A9)" ; 169 Copyright
"reg" #"^(AE)" ; 174 Registered trademark
"trade" #"^(2122)" ; 8482 Trademark
;-- Currency symbols
"curren" #"^(A4)" ; 164 Currency sign
"cent" #"^(A2)" ; 162 Cents
"pound" #"^(A3)" ; 163 British pounds
"euro" #"^(20AC)" ; 8364 Euro
"yen" #"^(A5)" ; 165 Yen
;-- Greek alphabet
"Alpha" #"^(391)" ; 913 UPPERCASE ALPHA
"alpha" #"^(3B1)" ; 945 lowercase alpha
"Beta" #"^(392)" ; 914 UPPERCASE BETA
"beta" #"^(3B2)" ; 946 lowercase beta
"Gamma" #"^(393)" ; 915 UPPERCASE GAMMA
"gamma" #"^(3B3)" ; 947 lowercase gamma
"Delta" #"^(394)" ; 916 UPPERCASE DELTA
"delta" #"^(3B4)" ; 948 lowercase delta
"Epsilon" #"^(395)" ; 917 UPPERCASE EPSILON
"epsilon" #"^(3B5)" ; 949 lowercase epsilon
"Zeta" #"^(396)" ; 918 UPPERCASE ZETA
"zeta" #"^(3B6)" ; 950 lowercase zeta
"Eta" #"^(397)" ; 919 UPPERCASE ETA
"eta" #"^(3B7)" ; 951 lowercase eta
"Theta" #"^(398)" ; 920 UPPERCASE THETA
"theta" #"^(3B8)" ; 952 lowercase theta
"thetasym" #"^(3D1)" ; 977 alternate lowercase theta
"Iota" #"^(399)" ; 921 UPPERCASE IOTA
"iota" #"^(3B9)" ; 953 lowercase iota
"Kappa" #"^(39A)" ; 922 UPPERCASE KAPPA
"kappa" #"^(3BA)" ; 954 lowercase kappa
"Lambda" #"^(39B)" ; 923 UPPERCASE LAMBDA
"lambda" #"^(3BB)" ; 955 lowercase lambda
"Mu" #"^(39C)" ; 924 UPPERCASE MU
"mu" #"^(3BC)" ; 956 lowercase mu
"Nu" #"^(39D)" ; 925 UPPERCASE NU
"nu" #"^(3BD)" ; 957 lowercase nu
"Xi" #"^(39E)" ; 926 UPPERCASE XI
"xi" #"^(3BE)" ; 958 lowercase xi
"Omicron" #"^(39F)" ; 927 UPPERCASE OMICRON
"omicron" #"^(3BF)" ; 959 lowercase omicron
"Pi" #"^(3A0)" ; 928 UPPERCASE PI
"pi" #"^(3C0)" ; 960 lowercase pi
"piv" #"^(3D6)" ; 982 alternative lowercase pi
"Rho" #"^(3A1)" ; 929 UPPERCASE RHO
"rho" #"^(3C1)" ; 961 lowercase rho
"Sigma" #"^(3A3)" ; 931 UPPERCASE SIGMA
"sigma" #"^(3C3)" ; 963 lowercase sigma
"sigmaf" #"^(3C2)" ; 962 final form lowercase sigma
"Tau" #"^(3A4)" ; 932 UPPERCASE TAU
"tau" #"^(3C4)" ; 964 lowercase tau
"Upsilon" #"^(3A5)" ; 933 UPPERCASE UPSILON
"upsilon" #"^(3C5)" ; 965 lowercase upsilon
"upsih" #"^(3D2)" ; 978 alternative lowercase upsilon
"Phi" #"^(3A6)" ; 934 UPPERCASE PHI
"phi" #"^(3C6)" ; 966 lowercase phi
"Chi" #"^(3A7)" ; 935 UPPERCASE CHI
"chi" #"^(3C7)" ; 967 lowercase chi
"Psi" #"^(3A8)" ; 936 UPPERCASE PSI
"psi" #"^(3C8)" ; 968 lowercase psi
"Omega" #"^(3A9)" ; 937 UPPERCASE OMEGA
"omega" #"^(3C9)" ; 969 lowercase omega
;-- Arrows
"larr" #"^(2190)" ; 8592 Left arrow
"uarr" #"^(2191)" ; 8593 Up arrow
"rarr" #"^(2192)" ; 8594 Right arrow
"darr" #"^(2193)" ; 8595 Down arrow
"harr" #"^(2194)" ; 8596 Left & right arrow
"crarr" #"^(21B5)" ; 8629 Carriage return arrow
;-- Spade, club, heart, diamond
"spades" #"^(2660)" ; 9824 Spade
"clubs" #"^(2663)" ; 9827 Club
"hearts" #"^(2665)" ; 9829 Heart
"diams" #"^(2666)" ; 9830 Diamond
;-- Accented letters
"Agrave" #"^(C0)" ; 192 CAPITAL A GRAVE ACCENT
"agrave" #"^(E0)" ; 224 lowercase a grave accent
"Aacute" #"^(C1)" ; 193 CAPITAL A ACUTE ACCENT
"aacute" #"^(E1)" ; 225 lowercase a acute accent
"Acirc" #"^(C2)" ; 194 CAPITAL A CIRCUMFLEX ACCENT
"acirc" #"^(E2)" ; 226 lowercase a circumflex accent
"Atilde" #"^(C3)" ; 195 CAPITAL A TILDE ACCENT
"atilde" #"^(E3)" ; 227 lowercase a tilde accent
"Auml" #"^(C4)" ; 196 CAPITAL A UMLAUT ACCENT
"auml" #"^(E4)" ; 228 lowercase a umlaut accent
"Aring" #"^(C5)" ; 197 CAPITAL A RING ABOVE ACCENT
"aring" #"^(E5)" ; 229 lowercase a ring accent
"AElig" #"^(C6)" ; 198 CAPITAL AE
"aelig" #"^(E6)" ; 230 lowercase ae
"Ccedil" #"^(C7)" ; 199 CAPITAL C CEDILLA ACCENT
"ccedil" #"^(E7)" ; 231 lowercase c cedilla accent
"Egrave" #"^(C8)" ; 200 CAPITAL E GRAVE ACCENT
"egrave" #"^(E8)" ; 232 lowercase e grave accent
"Eacute" #"^(C9)" ; 201 CAPITAL E ACUTE ACCENT
"eacute" #"^(E9)" ; 233 lowercase e acute accent
"Ecirc" #"^(CA)" ; 202 CAPITAL E CIRCUMFLEX ACCENT
"ecirc" #"^(EA)" ; 234 lowercase e circumflex accent
"ecirc" #"^(EA)" ; 234 lowercase e circumflex accent
"Euml" #"^(CB)" ; 203 CAPITAL E UMLAUT ACCENT
"euml" #"^(EB)" ; 235 lowercase e umlaut accent
"Igrave" #"^(CC)" ; 204 CAPITAL I GRAVE ACCENT
"igrave" #"^(EC)" ; 236 lowercase i grave accent
"Iacute" #"^(CD)" ; 205 CAPITAL I ACUTE ACCENT
"iacute" #"^(ED)" ; 237 lowercase i acute accent
"Icirc" #"^(CE)" ; 206 CAPITAL I CIRCUMFLEX ACCENT
"icirc" #"^(EE)" ; 238 lowercase i circumflex accent
"Iuml" #"^(CF)" ; 207 CAPITAL I UMLAUT ACCENT
"iuml" #"^(EF)" ; 239 lowercase i umlaut accent
"ETH" #"^(D0)" ; 208 CAPITAL ICELANDIC ETH
"eth" #"^(F0)" ; 240 lowercase Icelandic eth
"Ntilde" #"^(D1)" ; 209 CAPITAL N TILDE ACCENT
"ntilde" #"^(F1)" ; 241 lowercase n tilde accent
"Ograve" #"^(D2)" ; 210 CAPITAL O GRAVE ACCENT
"ograve" #"^(F2)" ; 242 lowercase o grave accent
"Oacute" #"^(D3)" ; 211 CAPITAL O ACUTE ACCENT
"oacute" #"^(F3)" ; 243 lowercase o acute accent
"Ocirc" #"^(D4)" ; 212 CAPITAL O CIRCUMFLEX ACCENT
"ocirc" #"^(F4)" ; 244 lowercase o circumflex accent
"Otilde" #"^(D5)" ; 213 CAPITAL O TILDE ACCENT
"otilde" #"^(F5)" ; 245 lowercase o tilde accent
"Ouml" #"^(D6)" ; 214 CAPITAL O UMLAUT ACCENT
"ouml" #"^(F6)" ; 246 lowercase o umlaut accent
"Oslash" #"^(D8)" ; 216 CAPITAL O SLASH ACCENT
"oslash" #"^(F8)" ; 248 lowercase o slash
"Ugrave" #"^(D9)" ; 217 CAPITAL U GRAVE ACCENT
"ugrave" #"^(F9)" ; 249 lowercase u grave accent
"Uacute" #"^(DA)" ; 218 CAPITAL U ACUTE ACCENT
"uacute" #"^(FA)" ; 250 lowercase u acute accent
"Ucirc" #"^(DB)" ; 219 CAPITAL U CIRCUMFLEX ACCENT
"ucirc" #"^(FB)" ; 251 lowercase u circumflex accent
"Uuml" #"^(DC)" ; 220 CAPITAL U UMLAUT
"uuml" #"^(FC)" ; 252 lowercase u umlaut accent
"Yacute" #"^(DD)" ; 221 CAPITAL Y ACUTE ACCENT
"yacute" #"^(FD)" ; 253 lowercase y acute accent
"yuml" #"^(FF)" ; 255 lowercase y umlaut accent
"THORN" #"^(DE)" ; 222 CAPITAL ICELANDIC THORN
"thorn" #"^(FE)" ; 254 lowercase Icelandic thorn
"szlig" #"^(DF)" ; 223 lowercase German sharp s
;-- Miscellaneous
"bull" #"^(2022)" ; 8226 Bullet
"hellip" #"^(2026)" ; 8230 Horizontal ellipsis
"fnof" #"^(192)" ; 402 lowercase Latin f with hook
"perp" #"^(22A5)" ; 8869 Perpendicular
"sdot" #"^(22C5)" ; 8901 Dot operator
"OElig" #"^(152)" ; 338 UPPERCASE LATIN OE LIGATURE
"oelig" #"^(153)" ; 339 lowercase Latin oe ligature
"Scaron" #"^(160)" ; 352 UPPERCASE S WITH CARON
"scaron" #"^(161)" ; 353 lowercase s with caron
"Yuml" #"^(178)" ; 376 CAPITAL Y WITH DIAERES
"circ" #"^(2C6)" ; 710 Circumflex accent
"tilde" #"^(2DC)" ; 732 Tilde (different from the tilde my keyboard generates)
"ndash" #"^(2013)" ; 8211 En dash
"mdash" #"^(2014)" ; 8212 Em dash
"lsquo" #"^(2018)" ; 8216 Left single quotation mark
"rsquo" #"^(2019)" ; 8217 Right single quotation mark
"sbquo" #"^(201A)" ; 8218 Single low-9 quotation mark
"ldquo" #"^(201C)" ; 8220 Left double quotation mark
"rdquo" #"^(201D)" ; 8221 Right double quotation mark
"bdquo" #"^(201E)" ; 8222 Double low-9 quotation mark
"dagger" #"^(2020)" ; 8224 Dagger
"Dagger" #"^(2021)" ; 8225 Double dagger
"permil" #"^(2030)" ; 8240 Per mille
"prime" #"^(2032)" ; 8242 Minutes (Degrees)
"Prime" #"^(2033)" ; 8243 Seconds (Degrees)
"lsaquo" #"^(2039)" ; 8249 Single left angle quotation
"rsaquo" #"^(2039)" ; 8249 Single right angle quotation
"oline" #"^(203E)" ; 8254 Overline
"lceil" #"^(2308)" ; 8968 Left ceiling
"rceil" #"^(2309)" ; 8969 Right ceiling
"lfloor" #"^(230A)" ; 8970 Left floor
"rfloor" #"^(230B)" ; 8971 Right floor
"loz" #"^(25CA)" ; 9674 Lozenge
"ensp" #"^(2002)" ; 8194 En space
"emsp" #"^(2003)" ; 8195 Em space
"thinsp" #"^(2009)" ; 8201 Thin space
"zwnj" #"^(200C)" ; 8204 Zero width non-joiner
"zwj" #"^(200D)" ; 8205 Zero width joiner
"lrm" #"^(200E)" ; 8206 Left-to-right mark
"rlm" #"^(200F)" ; 8207 Right-to-left mark
]
any-except-&: complement charset "&"
alphanum: system/catalog/bitsets/alpha-numeric
digits: system/catalog/bitsets/numeric
hex-digits: system/catalog/bitsets/hex-digits
register-codec [
name: 'html-entities
type: 'text
title: "Reserved characters in HTML"
decode: func [
{Creates a new string with possible HTML entities converted to chars}
text [string! binary! file!]
/local out s e char
] [
case [
file? text [text: read/string text]
binary? text [text: to string! text]
]
out: make string! length? text
parse text [
any [
s: some any-except-& e: ( append/part out s e )
| #"&" s: [
#"#" [
copy char 1 7 digits #";" (
char: attempt [to char! to integer! char]
)
| #"x" copy char some hex-digits #";" (
char: attempt [to char! to integer! debase char 16]
)
]
| copy char 1 10 alphanum #";" (
char: select/case html-entities char
)
| (char: none)
] e: (
unless char [char: #"&" e: :s]
append out char
) :e
]
]
out
]
]