NAME

XmParseMapping — Data type for a compound string parse mapping "XmParseMapping" "data types" "XmParseMapping"

SYNOPSIS

#include <Xm/Xm.h>

DESCRIPTION

XmParseMapping is an opaque data type for a parse mapping used by XmStringParseText to create a compound string. A parse mapping contains a pattern to be matched in text being parsed to create a compound string. It also contains a compound string, or a function to be invoked to provide a compound string, to be included in the compound string being created whenever the pattern is matched.

An application uses a resource-style interface to specify components for an XmParseMapping. XmParseMappingCreate creates a parse mapping, using a resource-style argument list. XmParseMappingGetValues and XmParseMappingSetValues retrieve and set the components of a parse mapping. XmParseMappingFree recovers memory used by a parse mapping. XmParseTable is an array of XmParseMapping objects.

The XmNinvokeParseProc resource is a function of type XmParseProc, which is defined as follows:

XmIncludeStatus (*XmParseProc) (text_in_out, text_end, type, tag, entry, pattern_length,
str_include, call_data)


        XtPointer *text_in_out;


        XtPointer text_end;


        XmTextType type;


        XmStringTag tag;


        XmParseMapping entry;


        int pattern_length;


        XmString *str_include;


        XtPointer call_data;

A parse procedure provides an escape mechanism for arbitrarily complex parsing. This procedure is invoked when a pattern in the input text is matched with a pattern in a parse mapping whose XmNincludeStatus is XmINVOKE.

The input text is a pointer to the first byte of the pattern that was matched to trigger the call to the parse procedure. The parse procedure consumes as many bytes of the input string as it needs and sets the input text pointer to the following byte. It returns a compound string to be included in the compound string being constructed, and it also returns an XmIncludeStatus indicating how the returned compound string should be handled. If the parse procedure does not set the input text pointer ahead by at least one byte, the parsing routine continues trying to match the input text with the patterns in the remaining parse mappings in the parse table. Otherwise, the parsing routine begins with the new input text pointer and tries to match the input text with patterns in the parse mappings starting at the beginning of the parse table.

text_in_out

Specifies the text being parsed. The value is a pointer to the first byte of text matching the pattern that triggered the call to the parse procedure. When the parse procedure returns, this argument is set to the position in the text where parsing should resume—that is, to the byte following the last character parsed by the parse procedure.

text_end

Specifies a pointer to the end of the text_in_out string. If text_end is NULL, the string is scanned until a NULL character is found. Otherwise, the string is scanned up to but not including the character whose address is text_end.

type

Specifies the type of text and the tag type. If a locale tag should be created, type has a value of either XmMULTIBYTE_TEXT or XmWIDECHAR_TEXT. If a charset should be created, type has a value of XmCHARSET_TEXT.

tag

Specifies the tag to be used in creating the result. The type of string tag created (charset or locale) depends on the text type and the passed in tag value. If the tag value is NULL and if type indicates that a charset string tag should be created, the string tag has the value that is the result of mapping XmSTRING_DEFAULT_CHARSET. If type indicates a locale string tag, the string tag has the value _MOTIF_DEFAULT_LOCALE.

entry

Specifies the parse mapping that triggered the call to the parse procedure.

pattern_length

Specifies the number of bytes in the input text, following text_in_out, that constitute the matched pattern.

str_include

Specifies a pointer to a compound string. The parse procedure creates a compound string to be included in the compound string being constructed. The parse procedure then returns the compound string in this argument.

call_data

Specifies data passed by the application to the parsing routine.

The parse procedure returns an XmIncludeStatus indicating how str_include is to be included in the compound string being constructed. Following are the possible values:

XmINSERT

Concatenate the result to the compound string being constructed and continue parsing.

XmTERMINATE

Concatenate the result to the compound string being constructed and terminate parsing.

RELATED

XmParseMappingCreate(3), XmParseMappingFree(3), XmParseMappingGetValues(3), XmParseMappingSetValues(3), XmParseTable(3), and XmString(3).