perl模塊之Smart::Comments

這個模塊用註釋的方式調試和跟蹤代碼，寫好了之後把use Smart::Comments去掉就可以了。

實驗

最後上代碼實驗大部分特性：

    [root@localhost Smart::Comments]# cat 1.pl 
    #!/usr/bin/env perl
    use strict;
    use Smart::Comments;


    my $date = "2014-05-01";

    #### Get: $date

    ### [<now>] Now...
    ### [<time>] Time...
    ### [<when>] When...
    ### Get time[<time>] 
    ### Get here[<here>] 
    ### Get file[<file>] 
    ### Get line[<line>] 

    my @values = (1..10);

    for (@values) {  #### Progress[===         ] % done 
    ### Round:$_
        do_sth($_);
    }
    sleep 1;
    ###　Compare lenth...
    my $len = length $date;
    ### require: $len > 11
    sub do_sth()
    {
        my $a =  shift;
        $a *= 2;
    }
    ### $date

    [root@localhost Smart::Comments]# perl 1.pl

    ### Get: '2014-05-01'

    ### [Thu May  1 22:38:49 2014] Now...
    ### [Thu May  1 22:38:49 2014] Time...
    ### [Thu May  1 22:38:49 2014] When...
    ### Get time[Thu May  1 22:38:49 2014] 
    ### Get here["1.pl", line 14] 
    ### Get file[1.pl] 
    ### Get line[16] 
    Progress[                ] 0% done                                   
    ### Round: 1
    Progress[=              ] 11% done                                   
    ### Round: 2
    Progress[===            ] 22% done                                   
    ### Round: 3
    Progress[=====          ] 33% done                                   
    ### Round: 4
    Progress[======         ] 44% done                                   
    ### Round: 5
    Progress[========       ] 55% done                                   
    ### Round: 6
    Progress[==========     ] 66% done                                   
    ### Round: 7
    Progress[===========    ] 77% done                                   
    ### Round: 8
    Progress[=============  ] 88% done                                   
    ### Round: 9


    ### Round: 10

    ### 　Compare lenth...

    ### $len > 11 was not true at 1.pl line 27.
    ###     $len was: 10

功能

1. 顯示變量的值
2. 跟蹤循環
3. 驗證斷言

用法

#!/usr/bin/env perl
use strict;
use Smart::Comments;
my $test = "Nice to meet you "
### $test

[root@localhost Smart::Comments]# perl 1.pl 
### $date: 'Nice to meet you '

使用3個#號，可以打印出後面的變量值 增加#號可以讓模塊更智能，最多5個#號

Debugging

### Label: Expression

打印變量值和標籤

### expression

打印變量

### text...
進度條

可以用<time> <here> <file> <line>

獲得時間，文件和行, 文件名，行

檢查和斷言

### require: BOOLEAN_EXPR

### assert: BOOLEAN_EXPR

### ensure: BOOLEAN_EXPR

### insist: BOOLEAN_EXPR

### require: $min < $result && $result < $max

如果表達式是假, 註釋就相當於執行die 命令，否者什麼都不做:

### $min < $result && $result < $max was not true at demo.pl line 86.
###     $min was: 7
###     $result was: 1000004
###     $max was: 99

### check: BOOLEAN_EXPR

### confirm: BOOLEAN_EXPR

### verify: BOOLEAN_EXPR

就是上面的warn的版本

進度條

foreach my VAR ( LIST ) {       ### Progressing...   done

for my VAR ( LIST ) {           ### Progressing...   done

foreach ( LIST ) {              ### Progressing...   done

for ( LIST ) {                  ### Progressing...   done

while (CONDITION) {             ### Progressing...   done

until (CONDITION) {             ### Progressing...   done

for (INIT; CONDITION; INCR) {   ### Progressing...   done

用C風格的循環，左邊的花括號{放在同一行，把註釋也放到這行

for (@candidates) {       ### Evaluating...     done

執行效果如下,模擬...到達右邊的字符

Evaluating                          done

Evaluating......                    done

Evaluating.............             done

Evaluating...................       done

Evaluating..........................done

當然可以把3個. 換成3個:、=、 |

也可以加入百分比的進度%

for (@candidates) {       ### Evaluating [===|    ] % done
效果如下
Evaluating [|                ]   0% done
Evaluating [===|             ]  25% done
Evaluating [========|        ]  50% done
Evaluating [============|    ]  75% done
Evaluating [=================] 100% done

for (@candidates) {       ### Evaluating |===[%]    |
效果如下
Evaluating |[0%]                       |
Evaluating |=[25%]                     |
Evaluating |========[50%]              |
Evaluating |===============[75%]       |
Evaluating |===========================|

對於開放式的循環，比如一個帶判斷的while循環，%就代表循環次數

時間估計

在for循環的註釋中，如果一次循環超過15秒，就會出現一個剩餘時間故事的框 比如

for (@seven_samurai) {      ### Fighting: [|||    ]
    fight();
    sleep 5;
}
效果：
Fighting: [                           ]
Fighting: [||||                       ]
Fighting: [|||||||||                  ]  (about 20 seconds remaining)
Fighting: [||||||||||||||             ]  (about 20 seconds remaining)
Fighting: [||||||||||||||||||         ]  (about 10 seconds 
Fighting: [|||||||||||||||||||||||    ]  (less than 10 seconds remaining)
Fighting: [|||||||||||||||||||||||||||]

依賴

都是核心模塊，所以直接down下來，編譯安裝就可以了

• Filter::Simple
• version.pm
• List::Util
• Data::Dumper
• Text::Balanced

參考

http://search.cpan.org/~dconway/Smart-Comments-1.000005/lib/Smart/Comments.pm