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).
+-----------------------------------------------------------------------+
| | XmParseMapping Resource Set | |
|Name | Class | Type | Default | Access |
+-------------------+-------+-----------------+----------------+--------+
|XmNclientData | | XtPointer | NULL | CSG |
+-------------------+-------+-----------------+----------------+--------+
|XmNincludeStatus | | XmIncludeStatus | XmINSERT | CSG |
+-------------------+-------+-----------------+----------------+--------+
|XmNinvokeParseProc | | XmParseProc | NULL | CSG |
+-------------------+-------+-----------------+----------------+--------+
|XmNpattern | | XtPointer | NULL | CSG |
+-------------------+-------+-----------------+----------------+--------+
|XmNpatternType | | XmTextType | XmCHARSET_TEXT | CSG |
+-------------------+-------+-----------------+----------------+--------+
|XmNsubstitute | | XmString | NULL | CSG |
+-------------------+-------+-----------------+----------------+--------+
+-------------------+-------+-----------------+----------------+--------+
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).
XmParseMapping(library call)