Related Syntax
declaration/definition	declare name-letters, name-letters

Syntax

  declare name-letters string string

A declaration used to identify an uppercase/lowercase relationship of characters above ASCII 127.

There are several constraints on this declaration:

• The two strings that are the arguments of the name-letters declaration must be of the same length
• The characters in the first string must be between "%128" and "%255".
• Characters can't be duplicated in the first string.
• Characters in the second string must be valid name characters: English letters, digits, ".","-","_" or "%128" to %255.
• No characters in the second string may have an English lowercase equivalent in the first string.

This means that:

• Every name character must be either lowercase or uppercase, but never both. A name character is lowercase if it is an English lowercase letter or if it appears in the first string in the declare name-letters declaration. A name character is uppercase if it is not lowercase.
• Every lowercase name character has a unique corresponding uppercase name character that is a different character than its lowercase version.
• Every uppercase English letter, digit, ".", "-", "_", the characters from the range "%128#" to "%225#" in the second argument, and the characters from the range "%128#" to "%225#" in neither the first or second argument, are all uppercase letters.

In the final analysis, an uppercase name character has zero, one, or more than one lowercase name character.

• There is no requirement to have a corresponding lowercase name character. This is typically for non-alphabetic characters: the digits and ".", "-", "_". Though, if these are specified, there may be lowercase values for these characters.
• An uppercase name character can have a single corresponding lowercase equivalent. This is typically the case in English letters, though again, it may be explicitly altered.
• An uppercase name character may have more than one lowercase equivalent. This typically occurs in languages with more forms of a lowercase version, usually by means of accents than by the uppercase name character.. French and Spanish are good examples of this.

This example defines the upper/lowercase relationship between all of the "accented" letters in the Latin 1 character set:

  declare name-letters
     "%10r{192,193,194,195,196,197,198,199,200,201}" _
     "%10r{202,203,204,205,206,207,208,209,210,211}" _
     "%10r{212,213,214,216,217,218,219,220,221,222}"

     "%10r{224,225,226,227,228,229,230,231,232,233}" _
     "%10r{234,235,236,237,238,239,240,241,242,243}" _
     "%10r{244,245,246,248,249,250,251,252,253,254}"