I've studied the demonstration script and I understand everything it's doing, except for this bit:

my $MAX_BYTES = 25;
my ($MIN_BPC, $MAX_BPC) = (1, 4);
my $MAX_CHARS = $MAX_BYTES / $MIN_BPC;

[download]

What's going on here? $MAX_CHARS will always be set to the value of $MAX_BYTES, and $MAX_BPC seems to serve no function. Am I right?

Also, what happens if, in the initial truncation of the string done using substr() as an lvalue, we land smack dab in the middle of a grapheme, and the rightmost character in the resultant truncated string is, by itself, a valid grapheme?

D:\>perl -CO -Mcharnames=:full -wE "$MAX = 4; $cafe = qq/cafe\N{COMBIN
+ING ACUTE ACCENT}/; say $cafe; substr($cafe, $MAX) = ''; say $cafe;" 
+> cafe.txt

D:\>

[download]

Here's the text in the output file cafe.txt:

café
cafe

(Thanks again for this very helpful script!)

In reply to Re^4: Best Way to Get Length of UTF-8 String in Bytes? by Jim
in thread Best Way to Get Length of UTF-8 String in Bytes? by Jim

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