Convert character + font shift to Unicode Plane 1 Mathematical Alphanumeric Symbols

which gives:

𝔓𝔩𝔞𝔫𝔢1ℭ𝔬𝔫𝔳𝔢𝔯𝔱𝔢𝔯

• The first argument is a string; all ASCII alphabetic characters (and, if supported, numeric characters, and Greek characters) are converted to the Unicode Plane 1 Mathematical Alphanumeric Symbols character corresponding to the font shift named in the second argument. The gem also supports the Enclosed Alphanumerics and Enclosed Alphanumeric Supplement blocks, and circled numbers in Dingbats,

• Characters are assumed to be in UTF-8; if characters are escaped for representation in ASCII, they need to be converted to UTF-8 before being passed to this gem.

• The string is converted one character at a time: multi-character dingbats such as DINGBAT CIRCLED SANS-SERIF NUMBER TEN (U+2789) (➉) are not supported.

• Other characters mapped to Mathematical Alphanumeric Symbols are also supported, including:

  • U+0131 LATIN SMALL LETTER DOTLESS I (ı)

  • U+0237 LATIN SMALL LETTER DOTLESS J (ȷ)

  • U+03F4 GREEK CAPITAL THETA SYMBOL (ϴ)

  • U+2207 NABLA (∇)

  • U+2202 PARTIAL DIFFERENTIAL (∂)

  • U+03F5 GREEK LUNATE EPSILON SYMBOL (ϵ)

  • U+03D1 GREEK THETA SYMBOL (ϑ)

  • U+03F0 GREEK KAPPA SYMBOL (ϰ)

  • U+03D5 GREEK PHI SYMBOL (ϕ)

  • U+03F1 GREEK RHO SYMBOL (ϱ)

  • U+03D6 GREEK PI SYMBOL (ϖ)

  • U+03DC GREEK LETTER DIGAMMA (Ϝ)

  • U+03DD GREEK SMALL LETTER DIGAMMA (ϝ)

• If a character is not supported in the specified font shift, it is left as is.

• Legal values supported for the second argument are:

  :fraktur

  Fraktur Normal

  :frakturbold

  Fraktur Bold

  :monospace

  Monospace

  :doublestruck

  Double-Struck

  :script

  Script

  :scriptbold

  Script Bold

  :circled

  Circled

  :circledblack

  Circled Black

  :squared

  Squared

  :squaredblack

  Squared Black

  :serifbold

  Serifed Bold

  :serifitalic

  Serifed Italic

  :serifbolditalic

  Serifed Bold Italic

  :sans

  Sans-Serif

  :sansbold

  Sans-Serif Bold

  :sansitalic

  Sans-Serif Italic

  :sansbolditalic

  Sans-Serif Bold Italic

• Illegal values for the second argument will raise an error.

• The base mapping is taken from http://textconverter.net/js/app.300d38d3.js