Commit | Line | Data |
---|---|---|
0e74ff8e JH |
1 | #!./perl -w |
2 | ||
3 | BEGIN { | |
4 | chdir 't' if -d 't'; | |
5 | @INC = '../lib'; | |
6 | } | |
7 | ||
8 | use warnings; | |
9 | use strict; | |
10 | use vars qw($foo $bar $baz $ballast); | |
11 | use Test::More tests => 159; | |
12 | ||
13 | use Benchmark qw(:all); | |
14 | ||
15 | my $delta = 0.2; | |
16 | ||
17 | # Some timing ballast | |
18 | sub fib { | |
19 | my $n = shift; | |
20 | return $n if $n < 2; | |
21 | fib($n-1) + fib($n-2); | |
22 | } | |
23 | $ballast = 15; | |
24 | ||
25 | my $all_pattern = | |
26 | qr/(\d+) +wallclock secs? +\( *(-?\d+\.\d\d) +usr +(-?\d+\.\d\d) +sys +\+ +(-?\d+\.\d\d) +cusr +(-?\d+\.\d\d) +csys += +(-?\d+\.\d\d) +CPU\)/; | |
27 | my $noc_pattern = | |
28 | qr/(\d+) +wallclock secs? +\( *(-?\d+\.\d\d) +usr +\+ +(-?\d+\.\d\d) +sys += +(-?\d+\.\d\d) +CPU\)/; | |
29 | my $nop_pattern = | |
30 | qr/(\d+) +wallclock secs? +\( *(-?\d+\.\d\d) +cusr +\+ +(-?\d+\.\d\d) +csys += +\d+\.\d\d +CPU\)/; | |
31 | # Please don't trust the matching parenthises to be useful in this :-) | |
32 | my $default_pattern = qr/$all_pattern|$noc_pattern/; | |
33 | ||
34 | my $t0 = new Benchmark; | |
35 | isa_ok ($t0, 'Benchmark', "Ensure we can create a benchmark object"); | |
36 | ||
37 | # We use the benchmark object once we've done some work: | |
38 | ||
39 | isa_ok(timeit(5, sub {++$foo}), 'Benchmark', "timeit CODEREF"); | |
40 | is ($foo, 5, "benchmarked code was run 5 times"); | |
41 | ||
42 | isa_ok(timeit(5, '++$bar'), 'Benchmark', "timeit eval"); | |
43 | is ($bar, 5, "benchmarked code was run 5 times"); | |
44 | ||
45 | print "# Burning CPU to benchmark things will take time...\n"; | |
46 | ||
47 | ||
48 | ||
49 | # We need to do something fairly slow in the coderef. | |
50 | # Same coderef. Same place in memory. | |
51 | my $coderef = sub {$baz += fib($ballast)}; | |
52 | ||
53 | # The default is three. | |
54 | $baz = 0; | |
55 | my $threesecs = countit(0, $coderef); | |
56 | isa_ok($threesecs, 'Benchmark', "countit 0, CODEREF"); | |
57 | isnt ($baz, 0, "benchmarked code was run"); | |
58 | my $in_threesecs = $threesecs->iters; | |
59 | print "# $in_threesecs iterations\n"; | |
60 | ok ($in_threesecs > 0, "iters returned positive iterations"); | |
61 | ||
62 | my $estimate = int ($in_threesecs / 3); | |
63 | print "# from the 3 second run estimate $estimate iterations in 1 second...\n"; | |
64 | $baz = 0; | |
65 | my $onesec = countit(1, $coderef); | |
66 | isa_ok($onesec, 'Benchmark', "countit 1, CODEREF"); | |
67 | isnt ($baz, 0, "benchmarked code was run"); | |
68 | my $in_onesec = $onesec->iters; | |
69 | print "# $in_onesec iterations\n"; | |
70 | ok ($in_onesec > 0, "iters returned positive iterations"); | |
71 | ||
72 | my $difference = $in_onesec - $estimate; | |
73 | ok (abs ($difference / $in_onesec) < $delta, | |
74 | "is $in_onesec within $delta of estimate ($estimate)"); | |
75 | ||
76 | # I found that the eval'ed version was 3 times faster than the coderef. | |
77 | # (now it has a different ballast value) | |
78 | $baz = 0; | |
79 | my $again = countit(1, '$baz += fib($ballast)'); | |
80 | isa_ok($onesec, 'Benchmark', "countit 1, eval"); | |
81 | isnt ($baz, 0, "benchmarked code was run"); | |
82 | my $in_again = $again->iters; | |
83 | print "# $in_again iterations\n"; | |
84 | ok ($in_again > 0, "iters returned positive iterations"); | |
85 | ||
86 | ||
87 | my $t1 = new Benchmark; | |
88 | isa_ok ($t1, 'Benchmark', "Create another benchmark object now we're finished"); | |
89 | ||
90 | my $diff = timediff ($t1, $t0); | |
91 | isa_ok ($diff, 'Benchmark', "Get the time difference"); | |
92 | isa_ok (timesum ($t0, $t1), 'Benchmark', "check timesum"); | |
93 | ||
94 | my $default = timestr ($diff); | |
95 | isnt ($default, '', 'timestr ($diff)'); | |
96 | my $auto = timestr ($diff, 'auto'); | |
97 | is ($auto, $default, 'timestr ($diff, "auto") matches timestr ($diff)'); | |
98 | ||
99 | { | |
100 | my $all = timestr ($diff, 'all'); | |
101 | like ($all, $all_pattern, 'timestr ($diff, "all")'); | |
102 | print "# $all\n"; | |
103 | ||
104 | my ($wallclock, $usr, $sys, $cusr, $csys, $cpu) = $all =~ $all_pattern; | |
105 | ||
106 | is (timestr ($diff, 'none'), '', "none supresses output"); | |
107 | ||
108 | my $noc = timestr ($diff, 'noc'); | |
109 | like ($noc, qr/$wallclock +wallclock secs? +\( *$usr +usr +\+ +$sys +sys += +$cpu +CPU\)/, 'timestr ($diff, "noc")'); | |
110 | ||
111 | my $nop = timestr ($diff, 'nop'); | |
112 | like ($nop, qr/$wallclock +wallclock secs? +\( *$cusr +cusr +\+ +$csys +csys += +\d+\.\d\d +CPU\)/, 'timestr ($diff, "nop")'); | |
113 | ||
114 | if ($auto eq $noc) { | |
115 | pass ('"auto" is "noc"'); | |
116 | } else { | |
117 | is ($auto, $all, '"auto" isn\'t "noc", so should be eq to "all"'); | |
118 | } | |
119 | ||
120 | like (timestr ($diff, 'all', 'E'), | |
121 | qr/(\d+) +wallclock secs? +\( *\d\.\d+E[-+]?\d\d\d? +usr +\d\.\d+E[-+]?\d\d\d? +sys +\+ +\d\.\d+E[-+]?\d\d\d? +cusr +\d\.\d+E[-+]?\d\d\d? +csys += +\d\.\d+E[-+]?\d\d\d? +CPU\)/, 'timestr ($diff, "all", "E") [sprintf format of "E"]'); | |
122 | } | |
123 | ||
124 | my $out = tie *OUT, 'TieOut'; | |
125 | ||
126 | my $iterations = 3; | |
127 | ||
128 | $foo = 0; | |
129 | select(OUT); | |
130 | my $got = timethis($iterations, sub {++$foo}); | |
131 | select(STDOUT); | |
132 | isa_ok($got, 'Benchmark', "timethis CODEREF"); | |
133 | is ($foo, $iterations, "benchmarked code was run $iterations times"); | |
134 | ||
135 | $got = $out->read(); | |
136 | like ($got, qr/^timethis $iterations/, 'default title'); | |
137 | like ($got, $default_pattern, 'default format is all or noc'); | |
138 | ||
139 | $bar = 0; | |
140 | select(OUT); | |
141 | $got = timethis($iterations, '++$bar'); | |
142 | select(STDOUT); | |
143 | isa_ok($got, 'Benchmark', "timethis eval"); | |
144 | is ($bar, $iterations, "benchmarked code was run $iterations times"); | |
145 | ||
146 | $got = $out->read(); | |
147 | like ($got, qr/^timethis $iterations/, 'default title'); | |
148 | like ($got, $default_pattern, 'default format is all or noc'); | |
149 | ||
150 | my $title = 'lies, damn lies and benchmarks'; | |
151 | $foo = 0; | |
152 | select(OUT); | |
153 | $got = timethis($iterations, sub {++$foo}, $title); | |
154 | select(STDOUT); | |
155 | isa_ok($got, 'Benchmark', "timethis with title"); | |
156 | is ($foo, $iterations, "benchmarked code was run $iterations times"); | |
157 | ||
158 | $got = $out->read(); | |
159 | like ($got, qr/^$title:/, 'specify title'); | |
160 | like ($got, $default_pattern, 'default format is all or noc'); | |
161 | ||
162 | # default is auto, which is all or noc. nop can never match the default | |
163 | $foo = 0; | |
164 | select(OUT); | |
165 | $got = timethis($iterations, sub {++$foo}, $title, 'nop'); | |
166 | select(STDOUT); | |
167 | isa_ok($got, 'Benchmark', "timethis with format"); | |
168 | is ($foo, $iterations, "benchmarked code was run $iterations times"); | |
169 | ||
170 | $got = $out->read(); | |
171 | like ($got, qr/^$title:/, 'specify title'); | |
172 | like ($got, $nop_pattern, 'specify format as nop'); | |
173 | ||
174 | { | |
175 | $foo = 0; | |
176 | select(OUT); | |
177 | my $start = time; | |
178 | $got = timethis(-2, sub {$foo+= fib($ballast)}, $title, 'none'); | |
179 | my $end = time; | |
180 | select(STDOUT); | |
181 | isa_ok($got, 'Benchmark', | |
182 | "timethis, at least 2 seconds with format 'none'"); | |
183 | ok ($foo > 0, "benchmarked code was run"); | |
184 | ok ($end - $start > 1, "benchmarked code ran for over 1 second"); | |
185 | ||
186 | $got = $out->read(); | |
187 | # Remove any warnings about having too few iterations. | |
188 | $got =~ s/\(warning:[^\)]+\)//gs; | |
189 | $got =~ s/^[ \t\n]+//s; # Remove all the whitespace from the beginning | |
190 | ||
191 | is ($got, '', "format 'none' should suppress output"); | |
192 | } | |
193 | ||
194 | $foo = $bar = $baz = 0; | |
195 | select(OUT); | |
196 | $got = timethese($iterations, { Foo => sub {++$foo}, Bar => '++$bar', | |
197 | Baz => sub {++$baz} }); | |
198 | select(STDOUT); | |
199 | is(ref ($got), 'HASH', "timethese should return a hashref"); | |
200 | isa_ok($got->{Foo}, 'Benchmark', "Foo value"); | |
201 | isa_ok($got->{Bar}, 'Benchmark', "Bar value"); | |
202 | isa_ok($got->{Baz}, 'Benchmark', "Baz value"); | |
203 | eq_set([keys %$got], [qw(Foo Bar Baz)], 'should be exactly three objects'); | |
204 | is ($foo, $iterations, "Foo code was run $iterations times"); | |
205 | is ($bar, $iterations, "Bar code was run $iterations times"); | |
206 | is ($baz, $iterations, "Baz code was run $iterations times"); | |
207 | ||
208 | $got = $out->read(); | |
209 | # Remove any warnings about having too few iterations. | |
210 | $got =~ s/\(warning:[^\)]+\)//gs; | |
211 | ||
212 | like ($got, qr/timing $iterations iterations of\s+Bar\W+Baz\W+Foo\W*?\.\.\./s, | |
213 | 'check title'); | |
214 | # Remove the title | |
215 | $got =~ s/.*\.\.\.//s; | |
216 | like ($got, qr/\bBar\b.*\bBaz\b.*\bFoo\b/s, 'check output is in sorted order'); | |
217 | like ($got, $default_pattern, 'should find default format somewhere'); | |
218 | ||
219 | my $code_to_test = { Foo => sub {$foo+=fib($ballast-2)}, | |
220 | Bar => sub {$bar+=fib($ballast)}}; | |
221 | # Keep these for later. | |
222 | my $results; | |
223 | { | |
224 | $foo = $bar = 0; | |
225 | select(OUT); | |
226 | my $start = times; | |
227 | $results = timethese(-0.1, $code_to_test, 'none'); | |
228 | my $end = times; | |
229 | select(STDOUT); | |
230 | ||
231 | is(ref ($results), 'HASH', "timethese should return a hashref"); | |
232 | isa_ok($results->{Foo}, 'Benchmark', "Foo value"); | |
233 | isa_ok($results->{Bar}, 'Benchmark', "Bar value"); | |
234 | eq_set([keys %$results], [qw(Foo Bar)], 'should be exactly two objects'); | |
235 | ok ($foo > 0, "Foo code was run"); | |
236 | ok ($bar > 0, "Bar code was run"); | |
237 | ||
238 | ok (($end - $start) > 0.1, "benchmarked code ran for over 0.1 seconds"); | |
239 | ||
240 | $got = $out->read(); | |
241 | # Remove any warnings about having too few iterations. | |
242 | $got =~ s/\(warning:[^\)]+\)//gs; | |
243 | is ($got =~ tr/ \t\n//c, 0, "format 'none' should suppress output"); | |
244 | } | |
245 | my $graph_dissassembly = | |
246 | qr!^[ \t]+(\S+)[ \t]+(\w+)[ \t]+(\w+)[ \t]* # Title line | |
247 | \n[ \t]*(\w+)[ \t]+([0-9.]+(?:/s)?)[ \t]+(-+)[ \t]+(-?\d+%)[ \t]* | |
248 | \n[ \t]*(\w+)[ \t]+([0-9.]+(?:/s)?)[ \t]+(-?\d+%)[ \t]+(-+)[ \t]*$!xm; | |
249 | ||
250 | sub check_graph_consistency { | |
251 | my ( $ratetext, $slowc, $fastc, | |
252 | $slowr, $slowratet, $slowslow, $slowfastt, | |
253 | $fastr, $fastratet, $fastslowt, $fastfast) | |
254 | = @_; | |
255 | is ($slowc, $slowr, "left col tag should be top row tag"); | |
256 | is ($fastc, $fastr, "right col tag should be bottom row tag"); | |
257 | like ($slowslow, qr/^-+/, "should be dash for comparing slow with slow"); | |
258 | is ($slowslow, $fastfast, "slow v slow should be same as fast v fast"); | |
259 | my $slowrate = $slowratet; | |
260 | my $fastrate = $fastratet; | |
261 | my ($slow_is_rate, $fast_is_rate); | |
262 | unless ($slow_is_rate = $slowrate =~ s!/s!!) { | |
263 | # Slow is expressed as iters per second. | |
264 | $slowrate = 1/$slowrate if $slowrate; | |
265 | } | |
266 | unless ($fast_is_rate = $fastrate =~ s!/s!!) { | |
267 | # Fast is expressed as iters per second. | |
268 | $fastrate = 1/$fastrate if $fastrate; | |
269 | } | |
270 | if ($ratetext =~ /rate/i) { | |
271 | ok ($slow_is_rate, "slow should be expressed as a rate"); | |
272 | ok ($fast_is_rate, "fast should be expressed as a rate"); | |
273 | } else { | |
274 | ok (!$slow_is_rate, "slow should be expressed as a iters per second"); | |
275 | ok (!$fast_is_rate, "fast should be expressed as a iters per second"); | |
276 | } | |
277 | ||
278 | (my $slowfast = $slowfastt) =~ s!%!!; | |
279 | (my $fastslow = $fastslowt) =~ s!%!!; | |
280 | if ($slowrate < $fastrate) { | |
281 | pass ("slow rate is less than fast rate"); | |
282 | ok ($slowfast < 0 && $slowfast > -100, | |
283 | "slowfast should be less than zero, and > -100"); | |
e5967bfd MS |
284 | ok ($fastslow > 100, "fastslow should be > 100") || |
285 | print STDERR "# fastslow $fastslow\n"; | |
0e74ff8e JH |
286 | } else { |
287 | is ($slowrate, $fastrate, | |
288 | "slow rate isn't less than fast rate, so should be the same"); | |
289 | is ($slowfast, 0, "slowfast should be zero"); | |
290 | is ($fastslow, 0, "fastslow should be zero"); | |
291 | } | |
292 | } | |
293 | ||
294 | sub check_graph_vs_output { | |
295 | my ($chart, $got) = @_; | |
296 | my ( $ratetext, $slowc, $fastc, | |
297 | $slowr, $slowratet, $slowslow, $slowfastt, | |
298 | $fastr, $fastratet, $fastslowt, $fastfast) | |
299 | = $got =~ $graph_dissassembly; | |
300 | check_graph_consistency ( $ratetext, $slowc, $fastc, | |
301 | $slowr, $slowratet, $slowslow, $slowfastt, | |
302 | $fastr, $fastratet, $fastslowt, $fastfast); | |
303 | is_deeply ($chart, [['', $ratetext, $slowc, $fastc], | |
304 | [$slowr, $slowratet, $slowslow, $slowfastt], | |
305 | [$fastr, $fastratet, $fastslowt, $fastfast]], | |
306 | "check the chart layout matches the formatted output"); | |
307 | } | |
308 | ||
309 | sub check_graph { | |
310 | my ($title, $row1, $row2) = @_; | |
311 | is (scalar @$title, 4, "Four entries in title row"); | |
312 | is (scalar @$row1, 4, "Four entries in first row"); | |
313 | is (scalar @$row2, 4, "Four entries in second row"); | |
314 | is (shift @$title, '', "First entry of output graph should be ''"); | |
315 | check_graph_consistency (@$title, @$row1, @$row2); | |
316 | } | |
317 | ||
318 | { | |
319 | select(OUT); | |
320 | my $start = times; | |
321 | my $chart = cmpthese( -0.1, { a => "++\$i", b => "\$i *= 2" } ) ; | |
322 | my $end = times; | |
323 | select(STDOUT); | |
324 | ok (($end - $start) > 0.05, "benchmarked code ran for over 0.05 seconds"); | |
325 | ||
326 | $got = $out->read(); | |
327 | # Remove any warnings about having too few iterations. | |
328 | $got =~ s/\(warning:[^\)]+\)//gs; | |
329 | ||
330 | like ($got, qr/running\W+a\W+b.*?for at least 0\.1 CPU second/s, | |
331 | 'check title'); | |
332 | # Remove the title | |
333 | $got =~ s/.*\.\.\.//s; | |
334 | like ($got, $default_pattern, 'should find default format somewhere'); | |
335 | like ($got, $graph_dissassembly, "Should find the output graph somewhere"); | |
336 | check_graph_vs_output ($chart, $got); | |
337 | } | |
338 | ||
339 | { | |
340 | $foo = $bar = 0; | |
341 | select(OUT); | |
342 | my $chart = cmpthese( 10, $code_to_test, 'nop' ) ; | |
343 | select(STDOUT); | |
344 | ok ($foo > 0, "Foo code was run"); | |
345 | ok ($bar > 0, "Bar code was run"); | |
346 | ||
347 | $got = $out->read(); | |
348 | # Remove any warnings about having too few iterations. | |
349 | $got =~ s/\(warning:[^\)]+\)//gs; | |
350 | like ($got, qr/timing 10 iterations of\s+Bar\W+Foo\W*?\.\.\./s, | |
351 | 'check title'); | |
352 | # Remove the title | |
353 | $got =~ s/.*\.\.\.//s; | |
354 | like ($got, $nop_pattern, 'specify format as nop'); | |
355 | like ($got, $graph_dissassembly, "Should find the output graph somewhere"); | |
356 | check_graph_vs_output ($chart, $got); | |
357 | } | |
358 | ||
359 | { | |
360 | $foo = $bar = 0; | |
361 | select(OUT); | |
362 | my $chart = cmpthese( 10, $code_to_test, 'none' ) ; | |
363 | select(STDOUT); | |
364 | ok ($foo > 0, "Foo code was run"); | |
365 | ok ($bar > 0, "Bar code was run"); | |
366 | ||
367 | $got = $out->read(); | |
368 | # Remove any warnings about having too few iterations. | |
369 | $got =~ s/\(warning:[^\)]+\)//gs; | |
370 | $got =~ s/^[ \t\n]+//s; # Remove all the whitespace from the beginning | |
371 | is ($got, '', "format 'none' should suppress output"); | |
372 | is (ref $chart, 'ARRAY', "output should be an array ref"); | |
373 | # Some of these will go bang if the preceding test fails. There will be | |
374 | # a big clue as to why, from the previous test's diagnostic | |
375 | is (ref $chart->[0], 'ARRAY', "output should be an array of arrays"); | |
376 | check_graph (@$chart); | |
377 | } | |
378 | ||
379 | { | |
380 | $foo = $bar = 0; | |
381 | select(OUT); | |
382 | my $chart = cmpthese( $results ) ; | |
383 | select(STDOUT); | |
384 | is ($foo, 0, "Foo code was not run"); | |
385 | is ($bar, 0, "Bar code was not run"); | |
386 | ||
387 | $got = $out->read(); | |
388 | ok ($got !~ /\.\.\./s, 'check that there is no title'); | |
389 | like ($got, $graph_dissassembly, "Should find the output graph somewhere"); | |
390 | check_graph_vs_output ($chart, $got); | |
391 | } | |
392 | ||
393 | { | |
394 | $foo = $bar = 0; | |
395 | select(OUT); | |
396 | my $chart = cmpthese( $results, 'none' ) ; | |
397 | select(STDOUT); | |
398 | is ($foo, 0, "Foo code was not run"); | |
399 | is ($bar, 0, "Bar code was not run"); | |
400 | ||
401 | $got = $out->read(); | |
402 | is ($got, '', "'none' should suppress all output"); | |
403 | is (ref $chart, 'ARRAY', "output should be an array ref"); | |
404 | # Some of these will go bang if the preceding test fails. There will be | |
405 | # a big clue as to why, from the previous test's diagnostic | |
406 | is (ref $chart->[0], 'ARRAY', "output should be an array of arrays"); | |
407 | check_graph (@$chart); | |
408 | } | |
409 | ||
410 | ###}my $out = tie *OUT, 'TieOut'; my ($got); ### | |
411 | ||
412 | my $debug = tie *STDERR, 'TieOut'; | |
413 | ||
414 | $bar = 0; | |
415 | isa_ok(timeit(5, '++$bar'), 'Benchmark', "timeit eval"); | |
416 | is ($bar, 5, "benchmarked code was run 5 times"); | |
417 | is ($debug->read(), '', "There was no debug output"); | |
418 | ||
419 | Benchmark->debug(1); | |
420 | ||
421 | $bar = 0; | |
422 | select(OUT); | |
423 | $got = timeit(5, '++$bar'); | |
424 | select(STDOUT); | |
425 | isa_ok($got, 'Benchmark', "timeit eval"); | |
426 | is ($bar, 5, "benchmarked code was run 5 times"); | |
427 | is ($out->read(), '', "There was no STDOUT output with debug enabled"); | |
428 | isnt ($debug->read(), '', "There was STDERR debug output with debug enabled"); | |
429 | ||
430 | Benchmark->debug(0); | |
431 | ||
432 | $bar = 0; | |
433 | isa_ok(timeit(5, '++$bar'), 'Benchmark', "timeit eval"); | |
434 | is ($bar, 5, "benchmarked code was run 5 times"); | |
435 | is ($debug->read(), '', "There was no debug output debug disabled"); | |
436 | ||
437 | undef $debug; | |
438 | untie *STDERR; | |
439 | ||
440 | # To check the cache we are poking where we don't belong, inside the namespace. | |
441 | # The way benchmark is written We can't actually check whehter the cache is | |
442 | # being used, merely what's become cached. | |
443 | ||
444 | clearallcache(); | |
445 | my @before_keys = keys %Benchmark::cache; | |
446 | $bar = 0; | |
447 | isa_ok(timeit(5, '++$bar'), 'Benchmark', "timeit eval"); | |
448 | is ($bar, 5, "benchmarked code was run 5 times"); | |
449 | my @after5_keys = keys %Benchmark::cache; | |
450 | $bar = 0; | |
451 | isa_ok(timeit(10, '++$bar'), 'Benchmark', "timeit eval"); | |
452 | is ($bar, 10, "benchmarked code was run 10 times"); | |
453 | ok (!eq_array ([keys %Benchmark::cache], \@after5_keys), "10 differs from 5"); | |
454 | ||
455 | clearcache(10); | |
456 | # Hash key order will be the same if there are the same keys. | |
457 | is_deeply ([keys %Benchmark::cache], \@after5_keys, | |
458 | "cleared 10, only cached results for 5 should remain"); | |
459 | ||
460 | clearallcache(); | |
461 | is_deeply ([keys %Benchmark::cache], \@before_keys, | |
462 | "back to square 1 when we clear the cache again?"); | |
463 | ||
464 | ||
465 | package TieOut; | |
466 | ||
467 | sub TIEHANDLE { | |
468 | my $class = shift; | |
469 | bless(\( my $ref = ''), $class); | |
470 | } | |
471 | ||
472 | sub PRINT { | |
473 | my $self = shift; | |
474 | $$self .= join('', @_); | |
475 | } | |
476 | ||
477 | sub PRINTF { | |
478 | my $self = shift; | |
479 | $$self .= sprintf shift, @_; | |
480 | } | |
481 | ||
482 | sub read { | |
483 | my $self = shift; | |
484 | return substr($$self, 0, length($$self), ''); | |
485 | } |