XmParseMapping(3)

NAME
XmParseMapping — Data type for a compound string parse mapping

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.

  New Resources

The following table defines a set of resources used by the programmer to specify data. The codes in the access column indicate if the given resource can be set at creation time (C), set by using XmParseMappingSetValues (S), retrieved by using XmParseMappingGetValues (G), or is not applicable (N/A).

XmNclientData
    Specifies data to be used by the parse procedure.

XmNincludeStatus
    Specifies how the result of the mapping is to be included in the compound string being constructed. Unless the value is XmINVOKE, the result of the mapping is the value of XmNsubstitute. Following are the possible values for XmNincludeStatus:

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

    XmINVOKE
        Invoke the XmNinvokeParseProc on the text being parsed and use the returned compound string instead of XmNsubstitute as the result to be inserted into the compound string being constructed. The include status returned by the parse procedure (XmINSERT or XmTERMINATE) determines how the returned compound string is included.

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

XmNinvokeParseProc
    Specifies the parse procedure to be invoked when XmNincludeStatus is XmINVOKE.

XmNpattern
    Specifies a pattern to be matched in the text being parsed. This is a maximum of one character.

XmNpatternType
    Specifies the type of the pattern that is the value of XmNpattern. Following are the possible values:

    •   XmCHARSET_TEXT

    •   XmMULTIBYTE_TEXT

    •   XmWIDECHAR_TEXT

XmNsubstitute
    Specifies the compound string to be included in the compound string being constructed when XmNincludeStatus is XmINSERT or XmTERMINATE.

RELATED

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