Decimal numeric symbolic link not allowed: forbidden or text?

Question

According to HTML 5.1 specification :: Decimal numeric character reference:

The ampersand should be followed by the “#” character (U + 0023), followed by one or more ASCII digits representing an integer of ten , which corresponds to a Unicode code point, which is permitted as defined below . Then the numbers must be followed by ";" (U + 003B) character.

and below:

The numerical reference forms described above are allowed to refer to any Unicode code point, except for U + 0000, U + 000D, constantly undefined Unicode characters (not characters), surrogates (U + D800 - U + DFFF) and control characters, except for spaces.

I'm confused. Does this (bold text) mean that characters that cannot be referenced (for example, U + 000 or U + 00D) are forbidden or are simply treated as text , not as links?

TL DR Should I give an error checking entities that cannot be referenced, for example 
, or treat them as text?

Answer 1

8.2.4.69 The symbolic link designator says:

Otherwise, if the number is in the range 0xD800 to 0xDFFF or greater than 0x10FFFF, then this is a parse error . Return the character character U + FFFD REPLACEMENT CHARACTER.

, . , 0x0001 0x0008, 0x000D 0x001F, 0x007F 0x009F, 0xFDD0 0xFDEF 0x000B, 0xFFFE, 0xFFFF, 0x1FFFE, 0x1FFFF, 0x2FFFE, 0x2FFFF, 0x3FFFE, 0x3FFFF, 0x4FFFE, 0x4FFFF, 0x5FFFE, 0x5FFFF, 0x6FFFE, 0x6FFFF, 0x7FFFE, 0x7FFFF, 0x8FFFE, 0x8FFFF, 0x9FFFE, 0x9FFFF, 0xAFFFE, 0xAFFFF, 0xBFFFE, 0xBFFFF, 0xCFFFE, 0xCFFFF, 0xDFFFE, 0xDFFFF, 0xEFFFE, 0xEFFFF, 0xFFFFE, 0xFFFFF, 0x10FFFE 0x10FFFF, .

Answer 2

, , ( ?) - , , - :

, () , , , .

. .