diff options
| -rw-r--r-- | par/piece-table.scm | 20 | ||||
| -rw-r--r-- | par/piece-table.sld | 1 | ||||
| -rw-r--r-- | tests/piece-table.scm | 9 |
3 files changed, 22 insertions, 8 deletions
diff --git a/par/piece-table.scm b/par/piece-table.scm index a9b61f1..2892578 100644 --- a/par/piece-table.scm +++ b/par/piece-table.scm @@ -262,16 +262,20 @@ ;; From/to string (define string->piece-table make-piece-table) -(define (piece-table->string piece-table) - (let ((out-string (make-string (piece-table-text-length piece-table)))) +(define (piece-table-substring piece-table from to) + (let ((out-string (make-string (- to from)))) (let loop ((pieces (piece-table-pieces piece-table)) (acc 0)) - (if (null? pieces) + (if (or (null? pieces) (>= acc to)) out-string (let ((piece (car pieces))) - (string-copy! out-string - acc - (buffer->string (piece-buffer piece)) - (piece-start piece) - (+ (piece-start piece) (piece-length piece))) + (string-copy! + out-string + (max (- acc from) 0) + (buffer->string (piece-buffer piece)) + (+ (piece-start piece) (max (- from acc) 0)) + (+ (piece-start piece) (min (- to acc) (piece-length piece)))) (loop (cdr pieces) (+ acc (piece-length piece)))))))) + +(define (piece-table->string piece-table) + (piece-table-substring piece-table 0 (piece-table-text-length piece-table))) diff --git a/par/piece-table.sld b/par/piece-table.sld index 420175f..4650cb7 100644 --- a/par/piece-table.sld +++ b/par/piece-table.sld @@ -7,6 +7,7 @@ piece-table-insert! piece-table-delete! piece-table->string + piece-table-substring string->piece-table add-buffer-length) (include "piece-table.scm")) diff --git a/tests/piece-table.scm b/tests/piece-table.scm index d6c1105..317286c 100644 --- a/tests/piece-table.scm +++ b/tests/piece-table.scm @@ -21,6 +21,15 @@ (test-equal "HOLA910" (piece-table->string table)) (test-end "insert") +(test-begin "substring") + (parameterize ((add-buffer-length 10)) + (define table (make-piece-table "1234567890")) + (test-equal "1234567890" (piece-table-substring table 0 10)) + (test-equal "67890" (piece-table-substring table 5 10)) + (piece-table-insert! table 6 "X" 'normal) + (test-equal "6X78" (piece-table-substring table 5 9))) +(test-end "substring") + (test-begin "delete") (define table (make-piece-table "HOLA SOY EKAITZ")) (piece-table-delete! table 4 1) |