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The official levelDB does not support Cygwin platform, trying to compile it on Cygwin may get the error message:”Unknow platform”. Anyway, levelDB works on Windows Cygwin environment, all you have to do is to manually modify some files.

First, make sure your Cygwin has gcc-4 installed, not gcc-3:

$ gcc -v
gcc version 4.5.3 (GCC)

Then, edit build_detect_platform under levelDB source code folder, make it looks like this:

case "$TARGET_OS" in
    CYGWIN_*)
        PLATFORM=OS_LINUX
        COMMON_FLAGS="$MEMCMP_FLAG -lpthread -DOS_LINUX -DCYGWIN"
        PLATFORM_LDFLAGS="-lpthread"
        PORT_FILE=port/port_posix.cc
        ;;

The “CYGWIN_*” codes is added. Then edit port/port_posix.h, make it looks like this:

#if defined(OS_MACOSX) || defined(OS_SOLARIS) || defined(OS_FREEBSD) ||\
    defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_DRAGONFLYBSD) ||\
    defined(OS_ANDROID) || defined(OS_HPUX) || defined(CYGWIN)
// Use fread/fwrite/fflush on platforms without _unlocked variants
#define fread_unlocked fread
#define fwrite_unlocked fwrite
#define fflush_unlocked fflush
#endif

The ” || defined(CYGWIN)” is added, or you may got this error if you try to run make:

util/env_posix.cc:50: error: `fread_unlocked' undeclared (first use this function)

Now, you can compile levelDB on Windows Cygwin:

make

If you can find the file libleveldb.a in levelDB source code folder, it’s sucessfull. levelDB is just a library, not a standalone server, so we write a simple CPP code example to test it:

#include <iostream>
#include "leveldb/db.h"

int main(){
    leveldb::DB* db;
    leveldb::Options options;
    leveldb::Status status;

    options.create_if_missing = true;

    status = leveldb::DB::Open(options, "./testdb", &db);

    std::string key = "abc";
    std::string value = "123";
    std::string ret;
    std::cout << value;
    status = db->Put(leveldb::WriteOptions(), key, value);
    status = db->Get(leveldb::ReadOptions(), key, &ret);
    std::cout << ret;

    return 0;
}

Compile this code(file named a.cpp) and run with command:

g++ a.cpp -Iinclude -L. -lleveldb; ./a

I think PHP’s way to deal with float is too BAD!

PHP code:

$a = 12345678.123456;
echo (string) $a; echo "\n";
echo $a.''; echo "\n";
echo sprintf('%f', $a); echo "\n";

Outputs:

12345678.1235
12345678.1235
12345678.123456

The definition of “Dynamic Programming Language” must be redefined!

Strong typing if not dynamic

According to the current definition of “Dynamic Programming Language“, a language is called dynamic regardless if it is weak typing or not. But I think strong typing languages such as Python are not dynamic languages.

Consider what is the result of

1 + "2" = ?

Let’s see how mainstream programming languages treat this expression:

Most Python learners counldn’t understand why Python throw exception on such expression, why a “Dynamic Language” do so? PHP uses the dot mark “.” to concat strings, perfectly avoid the ambiguity of “+” operator in other language, and automicly convert string literal integer into int as people expected.

Be tolerant to null

Most programming languages terminate the execution when encounter statements as follows:

Object a = null;
Object v = a.b.c; // ?

PHP works fine as human expected(with ~E_NOTICE). Why should it terminates at getting null object’s properties? To make the code after keep running, programmers have to do lots of null checks, while all these checks can be eliminated.

This is how JavaScript does:

a = null;
if(a != undefined && a.b != undefined && a.b.c != undefined){
	v = a.b.c;
}

Programmers should write codes to take action only if it is in the expected condition, and ignore all unexpected conditions. A dynamic language runtime should not do force programmer to do uneccessary works.

Codes like

if(a.b.c == 1){
	// take action
}

is always prefered than

if(a != undefined && a.b != undefined && a.b.c != undefined){
	if(a.b.c == 1){
		// take action
	}
}

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1. Replace <?php comments_template(); ?> with

<?php
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else{comments_template();}
?>

2. Add pagination numbers

add this code to the comments.php file where you want the pagination numbers to be shown:

<?php if(function_exists('wptc_comments_pages')): ?>
	<p class="wptc_comments_pages"><?php wptc_comments_pages(); ?></p>
<?php endif; ?>

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• paged thread comments – needs wptc plugin

Help:

• http://www.ideawu.com/blog/

License:

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• You may NOT resell this theme
• The text “Theme by ideawu” and a link back to http://www.ideawu.com/blog/ must be retained in the footer, you may style it look smaller.

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