umutablecptrie.h File Reference

C API: This file defines a mutable Unicode code point trie. More...

`#include "unicode/utypes.h"`
`#include "unicode/ucpmap.h"`
`#include "unicode/ucptrie.h"`
`#include "unicode/utf8.h"`
`#include "unicode/localpointer.h"`

Go to the source code of this file.

## Namespaces

| icu
| File coll.h.

## Typedefs

typedef struct UMutableCPTrie | UMutableCPTrie
| Mutable Unicode code point trie. More...

## Functions

U_CAPI UMutableCPTrie * | umutablecptrie_open (uint32_t initialValue, uint32_t errorValue, UErrorCode *pErrorCode)
| Creates a mutable trie that initially maps each Unicode code point to the same value. More...
U_CAPI UMutableCPTrie * | umutablecptrie_clone (const UMutableCPTrie *other, UErrorCode *pErrorCode)
| Clones a mutable trie. More...
U_CAPI void | umutablecptrie_close (UMutableCPTrie *trie)
| Closes a mutable trie and releases associated memory. More...
U_CAPI UMutableCPTrie * | umutablecptrie_fromUCPMap (const UCPMap *map, UErrorCode *pErrorCode)
| Creates a mutable trie with the same contents as the UCPMap. More...
U_CAPI UMutableCPTrie * | umutablecptrie_fromUCPTrie (const UCPTrie *trie, UErrorCode *pErrorCode)
| Creates a mutable trie with the same contents as the immutable one. More...
U_CAPI uint32_t | umutablecptrie_get (const UMutableCPTrie *trie, UChar32 c)
| Returns the value for a code point as stored in the trie. More...
U_CAPI UChar32 | umutablecptrie_getRange (const UMutableCPTrie *trie, 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...
U_CAPI void | umutablecptrie_set (UMutableCPTrie *trie, UChar32 c, uint32_t value, UErrorCode *pErrorCode)
| Sets a value for a code point. More...
U_CAPI void | umutablecptrie_setRange (UMutableCPTrie *trie, UChar32 start, UChar32 end, uint32_t value, UErrorCode *pErrorCode)
| Sets a value for each code point [start..end]. More...
U_CAPI UCPTrie * | umutablecptrie_buildImmutable (UMutableCPTrie *trie, UCPTrieType type, UCPTrieValueWidth valueWidth, UErrorCode *pErrorCode)
| Compacts the data and builds an immutable UCPTrie according to the parameters. More...

## Detailed Description

C API: This file defines a mutable Unicode code point trie.

See also
  UCPTrie
  UMutableCPTrie

Definition in file umutablecptrie.h.

## Typedef Documentation

## UMutableCPTrie

typedef struct UMutableCPTrie UMutableCPTrie

Mutable Unicode code point trie.

Fast map from Unicode code points (U+0000..U+10FFFF) to 32-bit integer values. For details see https://icu.unicode.org/design/struct/utrie

Setting values (especially ranges) and lookup is fast. The mutable trie is only somewhat space-efficient. It builds a compacted, immutable UCPTrie.

This trie can be modified while iterating over its contents. For example, it is possible to merge its values with those from another set of ranges (e.g., another mutable or immutable trie): Iterate over those source ranges; for each of them iterate over this trie; add the source value into the value of each trie range.

See also
  UCPTrie
  umutablecptrie_buildImmutable

Stable:
  ICU 63

Definition at line 1 of file umutablecptrie.h.

## Function Documentation

## umutablecptrie_buildImmutable()

U_CAPI UCPTrie* umutablecptrie_buildImmutable | ( | UMutableCPTrie * | trie,
|  | UCPTrieType | type,
|  | UCPTrieValueWidth | valueWidth,
|  | UErrorCode * | pErrorCode
| ) |  |

Compacts the data and builds an immutable UCPTrie according to the parameters.

After this, the mutable trie will be empty.

The mutable trie stores 32-bit values until buildImmutable() is called. If values shorter than 32 bits are to be stored in the immutable trie, then the upper bits are discarded. For example, when the mutable trie contains values 0x81, -0x7f, and 0xa581, and the value width is 8 bits, then each of these is stored as 0x81 and the immutable trie will return that as an unsigned value. (Some implementations may want to make productive temporary use of the upper bits until buildImmutable() discards them.)

Not every possible set of mappings can be built into a UCPTrie, because of limitations resulting from speed and space optimizations. Every Unicode assigned character can be mapped to a unique value. Typical data yields data structures far smaller than the limitations.

It is possible to construct extremely unusual mappings that exceed the data structure limits. In such a case this function will fail with a U_INDEX_OUTOFBOUNDS_ERROR.

Parameters

  trie | the trie trie
  type | selects the trie type
  valueWidth | selects the number of bits in a trie data value; if smaller than 32 bits, then the values stored in the trie will be truncated first
  pErrorCode | an in/out ICU UErrorCode

See also
  umutablecptrie_fromUCPTrie

Stable:
  ICU 63

## umutablecptrie_clone()

U_CAPI UMutableCPTrie* umutablecptrie_clone | ( | const UMutableCPTrie * | other,
|  | UErrorCode * | pErrorCode
| ) |  |

Clones a mutable trie.

You must umutablecptrie_close() the clone once you are done using it.

Parameters

  other | the trie to clone
  pErrorCode | an in/out ICU UErrorCode

Returns
  the trie clone

Stable:
  ICU 63

## umutablecptrie_close()

U_CAPI void umutablecptrie_close | ( | UMutableCPTrie * | trie | ) |

Closes a mutable trie and releases associated memory.

Parameters

  trie | the trie

Stable:
  ICU 63

## umutablecptrie_fromUCPMap()

U_CAPI UMutableCPTrie* umutablecptrie_fromUCPMap | ( | const UCPMap * | map,
|  | UErrorCode * | pErrorCode
| ) |  |

Creates a mutable trie with the same contents as the UCPMap.

You must umutablecptrie_close() the mutable trie once you are done using it.

Parameters

  map | the source map
  pErrorCode | an in/out ICU UErrorCode

Returns
  the mutable trie

Stable:
  ICU 63

## umutablecptrie_fromUCPTrie()

U_CAPI UMutableCPTrie* umutablecptrie_fromUCPTrie | ( | const UCPTrie * | trie,
|  | UErrorCode * | pErrorCode
| ) |  |

Creates a mutable trie with the same contents as the immutable one.

You must umutablecptrie_close() the mutable trie once you are done using it.

Parameters

  trie | the immutable trie
  pErrorCode | an in/out ICU UErrorCode

Returns
  the mutable trie

Stable:
  ICU 63

## umutablecptrie_get()

U_CAPI uint32_t umutablecptrie_get | ( | const UMutableCPTrie * | trie,
|  | UChar32 | c
| ) |  |

Returns the value for a code point as stored in the trie.

Parameters

  trie | the trie
  c | the code point

Returns
  the value

Stable:
  ICU 63

## umutablecptrie_getRange()

U_CAPI UChar32 umutablecptrie_getRange | ( | const UMutableCPTrie * | trie,
|  | 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 trie. (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.)

The trie can be modified between calls to this function.

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.

See the same-signature ucptrie_getRange() for a code sample.

Parameters

  trie | the trie
  start | range start
  option | defines whether surrogates are treated normally, or as having the surrogateValue; usually UCPMAP_RANGE_NORMAL
  surrogateValue | value for surrogates; ignored if option==UCPMAP_RANGE_NORMAL
  filter | a pointer to a function that may modify the trie data value, or NULL if the values from the trie are to be used unmodified
  context | an opaque pointer that is passed on to the filter function
  pValue | if not NULL, receives the value that every code point start..end has; may have been modified by filter(context, trie 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

## umutablecptrie_open()

U_CAPI UMutableCPTrie* umutablecptrie_open | ( | uint32_t | initialValue,
|  | uint32_t | errorValue,
|  | UErrorCode * | pErrorCode
| ) |  |

Creates a mutable trie that initially maps each Unicode code point to the same value.

It uses 32-bit data values until umutablecptrie_buildImmutable() is called. umutablecptrie_buildImmutable() takes a valueWidth parameter which determines the number of bits in the data value in the resulting UCPTrie. You must umutablecptrie_close() the trie once you are done using it.

Parameters

  initialValue | the initial value that is set for all code points
  errorValue | the value for out-of-range code points and ill-formed UTF-8/16
  pErrorCode | an in/out ICU UErrorCode

Returns
  the trie

Stable:
  ICU 63

## umutablecptrie_set()

U_CAPI void umutablecptrie_set | ( | UMutableCPTrie * | trie,
|  | UChar32 | c,
|  | uint32_t | value,
|  | UErrorCode * | pErrorCode
| ) |  |

Sets a value for a code point.

Parameters

  trie | the trie
  c | the code point
  value | the value
  pErrorCode | an in/out ICU UErrorCode

Stable:
  ICU 63

## umutablecptrie_setRange()

U_CAPI void umutablecptrie_setRange | ( | UMutableCPTrie * | trie,
|  | UChar32 | start,
|  | UChar32 | end,
|  | uint32_t | value,
|  | UErrorCode * | pErrorCode
| ) |  |

Sets a value for each code point [start..end].

Faster and more space-efficient than setting the value for each code point separately.

Parameters

  trie | the trie
  start | the first code point to get the value
  end | the last code point to get the value (inclusive)
  value | the value
  pErrorCode | an in/out ICU UErrorCode

Stable:
  ICU 63