ICU 67.1  67.1
Typedefs | Enumerations | Functions
ucpmap.h File Reference

This file defines an abstract map from Unicode code points to integer values. More...

#include "unicode/utypes.h"

Go to the source code of this file.

Typedefs

typedef struct UCPMap UCPMap
 Abstract map from Unicode code points (U+0000..U+10FFFF) to integer values. More...
 
typedef uint32_t UCPMapValueFilter(const void *context, uint32_t value)
 Callback function type: Modifies a map value. More...
 

Enumerations

enum  UCPMapRangeOption { UCPMAP_RANGE_NORMAL, UCPMAP_RANGE_FIXED_LEAD_SURROGATES, UCPMAP_RANGE_FIXED_ALL_SURROGATES }
 Selectors for how ucpmap_getRange() etc. More...
 

Functions

U_CAPI uint32_t ucpmap_get (const UCPMap *map, UChar32 c)
 Returns the value for a code point as stored in the map, with range checking. More...
 
U_CAPI UChar32 ucpmap_getRange (const UCPMap *map, UChar32 start, UCPMapRangeOption option, uint32_t surrogateValue, UCPMapValueFilter *filter, const void *context, uint32_t *pValue)
 Returns the last code point such that all those from start to there have the same value. More...
 

Detailed Description

This file defines an abstract map from Unicode code points to integer values.

See also
UCPMap
UCPTrie
UMutableCPTrie

Definition in file ucpmap.h.

Typedef Documentation

◆ UCPMap

typedef struct UCPMap UCPMap

Abstract map from Unicode code points (U+0000..U+10FFFF) to integer values.

See also
UCPTrie
UMutableCPTrie
Stable:
ICU 63

Definition at line 31 of file ucpmap.h.

◆ UCPMapValueFilter

typedef uint32_t UCPMapValueFilter(const void *context, uint32_t value)

Callback function type: Modifies a map value.

Optionally called by ucpmap_getRange()/ucptrie_getRange()/umutablecptrie_getRange(). The modified value will be returned by the getRange function.

Can be used to ignore some of the value bits, make a filter for one of several values, return a value index computed from the map value, etc.

Parameters
contextan opaque pointer, as passed into the getRange function
valuea value from the map
Returns
the modified value
Stable:
ICU 63

Definition at line 114 of file ucpmap.h.

Enumeration Type Documentation

◆ UCPMapRangeOption

Selectors for how ucpmap_getRange() etc.

should report value ranges overlapping with surrogates. Most users should use UCPMAP_RANGE_NORMAL.

See also
ucpmap_getRange
ucptrie_getRange
umutablecptrie_getRange
Stable:
ICU 63
Enumerator
UCPMAP_RANGE_NORMAL 

ucpmap_getRange() enumerates all same-value ranges as stored in the map.

Most users should use this option.

Stable:
ICU 63
UCPMAP_RANGE_FIXED_LEAD_SURROGATES 

ucpmap_getRange() enumerates all same-value ranges as stored in the map, except that lead surrogates (U+D800..U+DBFF) are treated as having the surrogateValue, which is passed to getRange() as a separate parameter.

The surrogateValue is not transformed via filter(). See U_IS_LEAD(c).

Most users should use UCPMAP_RANGE_NORMAL instead.

This option is useful for maps that map surrogate code units to special values optimized for UTF-16 string processing or for special error behavior for unpaired surrogates, but those values are not to be associated with the lead surrogate code points.

Stable:
ICU 63
UCPMAP_RANGE_FIXED_ALL_SURROGATES 

ucpmap_getRange() enumerates all same-value ranges as stored in the map, except that all surrogates (U+D800..U+DFFF) are treated as having the surrogateValue, which is passed to getRange() as a separate parameter.

The surrogateValue is not transformed via filter(). See U_IS_SURROGATE(c).

Most users should use UCPMAP_RANGE_NORMAL instead.

This option is useful for maps that map surrogate code units to special values optimized for UTF-16 string processing or for special error behavior for unpaired surrogates, but those values are not to be associated with the lead surrogate code points.

Stable:
ICU 63

Definition at line 42 of file ucpmap.h.

Function Documentation

◆ ucpmap_get()

U_CAPI uint32_t ucpmap_get ( const UCPMap map,
UChar32  c 
)

Returns the value for a code point as stored in the map, with range checking.

Returns an implementation-defined error value if c is not in the range 0..U+10FFFF.

Parameters
mapthe map
cthe code point
Returns
the map value, or an implementation-defined error value if the code point is not in the range 0..U+10FFFF
Stable:
ICU 63

◆ ucpmap_getRange()

U_CAPI UChar32 ucpmap_getRange ( const UCPMap map,
UChar32  start,
UCPMapRangeOption  option,
uint32_t  surrogateValue,
UCPMapValueFilter filter,
const void *  context,
uint32_t *  pValue 
)

Returns the last code point such that all those from start to there have the same value.

Can be used to efficiently iterate over all same-value ranges in a map. (This is normally faster than iterating over code points and get()ting each value, but much slower than a data structure that stores ranges directly.)

If the UCPMapValueFilter function pointer is not NULL, then the value to be delivered is passed through that function, and the return value is the end of the range where all values are modified to the same actual value. The value is unchanged if that function pointer is NULL.

Example:

UChar32 start = 0, end;
uint32_t value;
while ((end = ucpmap_getRange(map, start, UCPMAP_RANGE_NORMAL, 0,
NULL, NULL, &value)) >= 0) {
// Work with the range start..end and its value.
start = end + 1;
}
Parameters
mapthe map
startrange start
optiondefines whether surrogates are treated normally, or as having the surrogateValue; usually UCPMAP_RANGE_NORMAL
surrogateValuevalue for surrogates; ignored if option==UCPMAP_RANGE_NORMAL
filtera pointer to a function that may modify the map data value, or NULL if the values from the map are to be used unmodified
contextan opaque pointer that is passed on to the filter function
pValueif not NULL, receives the value that every code point start..end has; may have been modified by filter(context, map value) if that function pointer is not NULL
Returns
the range end code point, or -1 if start is not a valid code point
Stable:
ICU 63