Man case pattern

From LSWiki

Files

/def/descriptor/case_pattern.c
/lib/descriptors/case_pattern.h

Description

Case pattern descriptors implement a mechanism that allows you to abstract the pattern of upper and lower case letters from a string, manipulate it in lower-case, and then restore the original case pattern when you are done. The way this usually goes is like so:

 #include <case_pattern.h>

 string text = get_some_text();
 descriptor pat = Case_Pattern_Extract(&text);
 text = transform_the_text_in_various_ways(text);
 text = Case_Pattern_Restore(text, pat);

Note that the argument to Case_Pattern_Extract() is being passed by reference. This causes it to be converted to lower-case. You do not have to pass the argument by reference if you do not want it to be converted to lower-case.

This is usually all you need to know about the mechanism; the fields of the descriptor and so forth are all managed internally. The remainder of this document is provided for reference purposes.

Public Fields

Case_Pattern_Type: The type of the case pattern. This is one of the following:

Case_Pattern_Type_Indeterminate: No representable case pattern was found in the original text. This generally means the original text contained no letters.

Case_Pattern_Type_All_Upper: All letters in the original text were upper-case.

Case_Pattern_Type_All_Lower: All letters in the original text were lower-case.

Case_Pattern_Type_First_Upper: The first letter in the original text was upper-case and the remainder were lower-case.

Case_Pattern_Type_First_Lower: The first letter in the original text was lower-case and the remainder were upper-case.

Case_Pattern_Type_Words_Upper: The original text had a capital letter at the beginning of each word, as if it were the output of the call capitalize_words(some_text).

Case_Pattern_Type_Main_Words_Upper: The original text had a capital letter at the beginning of each word, as if it were the output of the call capitalize_words(some_text, True).

Case_Pattern_Type_Complex: The original text had a complex case pattern, as specified in the Case_Pattern_Content field.

Case_Pattern_Original: The original text the case pattern is based on.

Case_Pattern_Altered: The text with the case pattern extracted (converted to lower-case).

Case_Pattern_Content: For Case_Pattern_Type_Complex patterns, an array describing the case pattern in the original text. Each element will be either Case_Pattern_Element_Upper, Case_Pattern_Element_Lower, or Case_Pattern_Neither, corresponding to one letter in the original text.

Internal Fields

Case_Pattern_Tag: The tag value for the descriptor system.

Support Functions

descriptor Case_Pattern_Extract(string text)

Extracts the case pattern from the specified text and returns it. If the text is passed by reference, it will be converted to lower-case.

string Case_Pattern_Restore(string text, descriptor dxr)

Coerces the specified text into the case pattern described by the descriptor passed and returns the result.

See Also

lower_case(efun), upper_case(efun), capitalize(efun), capitalize_words(sefun), descriptors(mechanisms)