+ Press n or j to go to the next uncovered block, b, p or k for the previous block. +
+ ++ Press n or j to go to the next uncovered block, b, p or k for the previous block. +
+ +| 1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +20 +21 +22 +23 +24 +25 +26 +27 +28 +29 +30 +31 +32 +33 +34 +35 +36 +37 +38 +39 +40 +41 +42 +43 +44 +45 +46 +47 | 1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x + | /** +* @license Apache-2.0 +* +* Copyright (c) 2024 The Stdlib Authors. +* +* Licensed under the Apache License, Version 2.0 (the "License"); +* you may not use this file except in compliance with the License. +* You may obtain a copy of the License at +* +* http://www.apache.org/licenses/LICENSE-2.0 +* +* Unless required by applicable law or agreed to in writing, software +* distributed under the License is distributed on an "AS IS" BASIS, +* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +* See the License for the specific language governing permissions and +* limitations under the License. +*/ + +'use strict'; + +/** +* Return the last `n` grapheme clusters (i.e., user-perceived characters) of a string. +* +* @module @stdlib/string/base/last-grapheme-cluster +* +* @example +* var last = require( '@stdlib/string/base/last-grapheme-cluster' ); +* +* var out = last( 'Hello', 1 ); +* // returns 'o'; +* +* out = last( 'JavaScript', 1 ); +* // returns 'Script'; +* +* out = last( '🐮🐷🐸🐵', 2 ); +* // returns '🐸🐵'; +*/ + +// MODULES // + +var main = require( './main.js' ); + + +// EXPORTS // + +module.exports = main; + |
+ Press n or j to go to the next uncovered block, b, p or k for the previous block. +
+ +| 1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +20 +21 +22 +23 +24 +25 +26 +27 +28 +29 +30 +31 +32 +33 +34 +35 +36 +37 +38 +39 +40 +41 +42 +43 +44 +45 +46 +47 +48 +49 +50 +51 +52 +53 +54 +55 +56 +57 +58 +59 +60 +61 +62 +63 +64 +65 +66 +67 +68 +69 +70 +71 +72 +73 +74 +75 +76 +77 +78 +79 +80 +81 +82 +83 +84 +85 +86 +87 +88 +89 +90 +91 +92 +93 +94 +95 +96 +97 +98 +99 +100 +101 +102 +103 +104 +105 +106 | 1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +1x +24x +24x +24x +24x +24x +24x +24x +4x +4x +20x +20x +20x +20x +24x +3x +3x +17x +17x +17x +17x +17x +17x +17x +17x +17x +17x +17x +17x +17x +17x +24x +92x +92x +92x +17x +17x +75x +75x +17x +17x +17x +17x +17x +24x +1x +1x +1x +1x +1x + | /**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var nextGraphemeClusterBreak = require( '@stdlib/string/next-grapheme-cluster-break' );
+var CircularBuffer = require( '@stdlib/utils/circular-buffer' );
+var zeros = require( '@stdlib/array/base/zeros' );
+
+
+// MAIN //
+
+/**
+* Returns the last `n` grapheme clusters (i.e., user-perceived characters) of a string.
+*
+* @param {string} str - input string
+* @param {NonNegativeInteger} n - number of grapheme clusters to return
+* @returns {string} output string
+*
+* @example
+* var out = last( 'Hello World', 1 );
+* // returns 'd'
+*
+* @example
+* var out = last( 'Evening', 3 );
+* // returns 'ing'
+*
+* @example
+* var out = last( 'JavaScript', 6 );
+* // returns 'Script'
+*
+* @example
+* var out = last( '六书/六書', 1 );
+* // returns '書'
+*
+* @example
+* var out = last( '🐶🐮🐷🐰🐸', 2 );
+* // returns '🐰🐸'
+*/
+function last( str, n ) {
+ var count;
+ var cbuf;
+ var buf;
+ var i;
+
+ if ( n === 0 || str === '' ) {
+ return '';
+ }
+ // Resolve the first cluster break:
+ i = nextGraphemeClusterBreak( str, 0 );
+
+ // If we received a sentinel value, return the input string, as there are no more cluster breaks to iterate over...
+ if ( i === -1 ) {
+ return str;
+ }
+ // Initialize a buffer for keeping track of cluster break indices:
+ buf = zeros( n );
+
+ // Wrap the buffer to create a circular buffer serving as a FIFO stack where we can keep at most `n` indices as we iterate from left-to-right:
+ cbuf = new CircularBuffer( buf );
+
+ // Add the first character index:
+ cbuf.push( 0 );
+
+ // Add the index of the first grapheme cluster break to our buffer:
+ cbuf.push( i );
+
+ // Slide a window over the string from left-to-right...
+ count = 0;
+ while ( true ) {
+ count += 1;
+ i = nextGraphemeClusterBreak( str, i );
+ if ( i === -1 ) {
+ break;
+ }
+ cbuf.push( i );
+ }
+ // Resolve the leftmost index:
+ i = buf[ (count+1)%n ]; // count+1 as count%n corresponds to the index of the "newest" element in the circular buffer and count+1 is the next element to replace (i.e., the "oldest" index)
+
+ // Return the last `n` grapheme clusters:
+ return str.substring( i );
+}
+
+
+// EXPORTS //
+
+module.exports = last;
+ |