Re: Just the facts about public ids, URNs, and URIs

[John Cowan <jcowan@reutershealth.com>]

I wrote:


>  Use a fixed font.

[unreadable mess removed]

Well, it looked all right leaving here!

I'll try again.

  Character Name(s)     Pubid    URN        URI     Status
  =================     =====    ===        ===     ======

LATIN CAPITAL LETTER ?   yes    upper     lowalpha  NORM
LATIN SMALL LETTER ?     yes    lower     upalpha   NORM
DIGIT *                  yes    number    digit     NORM
HYPHEN-MINUS             yes    other     mark      NORM
LEFT PARENTHESIS         yes    other     mark      NORM
RIGHT PARENTHESIS        yes    other     mark      NORM
FULL STOP                yes    other     mark      NORM
EXCLAMATION MARK         yes    other     mark      NORM
ASTERISK                 yes    other     mark      NORM
LOW LINE                 yes    other     mark      NORM
PLUS SIGN                yes    other     reserved  AVAIL
COMMA                    yes    other     reserved  AVAIL
COLON                    yes    other     reserved  AVAIL
EQUALS SIGN              yes    other     reserved  AVAIL
SEMICOLON                yes    other     reserved  AVAIL
COMMERCIAL AT            yes    other     reserved  AVAIL
DOLLAR SIGN              yes    other     reserved  AVAIL
QUESTION MARK            yes    reserved  reserved  ENCODE
SOLIDUS                  yes    reserved  reserved  ENCODE
NUMBER SIGN              yes    reserved  delims    ENCODE
PERCENT SIGN             yes    reserved  delims    ENCODE
SPACE                    yes    excluded  space     ENCODE
APOSTROPHE               yes    excluded  mark      ENCODE
AMPERSAND                no     excluded  reserved  AVAIL
TILDE                    no     excluded  mark      NULL
REVERSE SOLIDUS          no     excluded  delims    NULL
QUOTATION MARK           no     excluded  delims    NULL
LESS-THAN SIGN           no     excluded  delims    NULL
GREATER-THAN SIGN        no     excluded  delims    NULL
LEFT SQUARE BRACKET      no     excluded  unwise    NULL
RIGHT SQUARE BRACKET     no     excluded  unwise    NULL
CIRCUMFLEX               no     excluded  unwise    NULL
GRAVE ACCENT             no     excluded  unwise    NULL
LEFT CURLY BRACE         no     excluded  unwise    NULL
VERTICAL LINE            no     excluded  unwise    NULL
RIGHT CURLY BRACE        no     excluded  unwise    NULL


URN upper, lower, number, other: MAY be used without %-encoding.
URN reserved: SHOULD NOT be used without %-encoding.
URN excluded: MUST NOT be used without %-encoding.

URI lowalpha, upalpha, digits, mark: MAY be used without %-encoding;
    %-encoding MUST NOT affect semantics.
URI reserved: MAY be used without %-encoding;
    %-encoding MAY affect semantics.
URI space, delims, unwise: MUST NOT be used without %-encoding.

Status NORM: No encoding needed, can't be used as syntax.
Status ENCODE: MUST be encoded (%-encoded or privately).
Status AVAIL: Available for use as syntax character
    if literal use is %-encoded (AMPERSAND has no literal use).
Status NULL: Not usable in pubids, included for completeness.
-- 
There is / one art             || John Cowan <jcowan@reutershealth.com>
no more / no less              || http://www.reutershealth.com
to do / all things             || http://www.ccil.org/~cowan
with art- / lessness           \\ -- Piet Hein