จด The Art of Readable Code

var start = (new Date()).getTime(); // top of the page 
... 
var elapsed = (new Date()).getTime() - start; // bottom of the page 
document.writeln("Load time was: " + elapsed + " seconds"); 
var start_ms = (new Date()).getTime(); // top of the page 
... 
var elapsed_ms = (new Date()).getTime() - start_ms; // bottom of the page 
document.writeln("Load time was: " + elapsed_ms / 1000 + " seconds");

static const int kMaxOpenFiles = 100; 
class LogReader { 
public: 
    void OpenFile(string local_file); 
private: 
    int offset_; 
    DISALLOW_COPY_AND_ASSIGN(LogReader); 
};

var x = new DatePicker(); // DatePicker() is a "constructor" function 
var y = pageHeight(); // pageHeight() is an ordinary function

results = Database.all_objects.filter("year <= 2011")

CART_TOO_BIG_LIMIT = 10
if shopping_cart.num_items() >= CART_TOO_BIG_LIMIT: 
 Error("Too many items in cart.")

print integer_range(start=2, stop=4) 
# Does this print [2,3] or [2,3,4] (or something else)

set.PrintKeys(first="Bart", last="Maggie"

bool read_password = true;

class StatsKeeper { 
public: 
// A class for keeping track of a series of doubles 
 void Add(double d); // and methods for quick statistics about them 
 private: int count; /* how many so far  
*/ public: 
 double Average(); 
private: double minimum; 
list<double> 
 past_items 
 ;double maximum; 
};

// A class for keeping track of a series of doubles 
// and methods for quick statistics about them. 
class StatsKeeper { 
 public: 
     void Add(double d); 
     double Average(); 
 private: 
     list<double> past_items; 
     int count; // how many so far 
     double minimum; 
     double maximum; 
};

DatabaseConnection database_connection; 
string error; 
assert(ExpandFullName(database_connection, "Doug Adams", &error) 
 == "Mr. Douglas Adams"); 
assert(error == ""); 
assert(ExpandFullName(database_connection, " Jake Brown ", &error) 
 == "Mr. Jacob Brown III"); 
assert(error == ""); 
assert(ExpandFullName(database_connection, "No Such Guy", &error) == ""); 
assert(error == "no match found"); 
assert(ExpandFullName(database_connection, "John", &error) == ""); 
assert(error == "more than one result");

CheckFullName("Doug Adams", "Mr. Douglas Adams", ""); 
CheckFullName(" Jake Brown ", "Mr. Jake Brown III", ""); 
CheckFullName("No Such Guy", "", "no match found"); 
CheckFullName("John", "", "more than one result");

class FrontendServer { 
 public: 
 FrontendServer(); 
 void ViewProfile(HttpRequest* request); 
 void OpenDatabase(string location, string user); 
 void SaveProfile(HttpRequest* request); 
 string ExtractQueryParam(HttpRequest* request, string param); 
 void ReplyOK(HttpRequest* request, string html); 
 void FindFriends(HttpRequest* request); 
 void ReplyNotFound(HttpRequest* request, string error); 
 void CloseDatabase(string location); 
 ~FrontendServer(); 
};

class FrontendServer { 
 public: 
 FrontendServer(); 
 ~FrontendServer();

 // Handlers 
 void ViewProfile(HttpRequest* request); 
 void SaveProfile(HttpRequest* request); 
 void FindFriends(HttpRequest* request);

 // Request/Reply Utilities 
 string ExtractQueryParam(HttpRequest* request, string param); 
 void ReplyOK(HttpRequest* request, string html); 
 void ReplyNotFound(HttpRequest* request, string error);

// Database Helpers 
 void OpenDatabase(string location, string user); 
 void CloseDatabase(string location); 
};

# remove everything after the second '*' 
name = '*'.join(line.split('*')[:2])

/ Find a Node with the given 'name' or return NULL. 
// If depth <= 0, only 'subtree' is inspected. 
// If depth == N, only 'subtree' and N levels below are inspected.
Node* FindNodeInSubtree(Node* subtree, string name, int depth);

// Enforce limits on the Reply as stated in the Request, 
// such as the number of items returned, or total byte size, etc. 
void CleanReply(Request request, Reply reply);

NUM_THREADS = 8 # as long as it's >= 2 * num_processors, that's good enough.

// Impose a reasonable limit - no human can read that much anyway. 
const int MAX_RSS_SUBSCRIPTIONS = 1000;

image_quality = 0.72; // users thought 0.72 gave the best size/quality tradeoff

// The int is the CategoryType. 
// The first float in the inner pair is the 'score', 
// the second is the 'weight'. 
typedef hash_map<int, pair<float, float> > ScoreMap;

// CategoryType -> (score, weight) 
typedef hash_map<int, pair<float, float> > ScoreMap;

// Return the number of lines in this file. 
int CountLines(string filename) { ... }

// Count how many newline bytes ('\n') are in the file. 
int CountLines(string filename) { ... }

if (a == b) { 
 // Case One ... 
} else { 
 // Case Two ... 
}

if (a != b) { 
 // Case Two ... 
} else { 
 // Case One ... 
}

public boolean Contains(String str, String substr) { 
     if (str == null || substr == null) return false; 
     if (substr.equals("")) return true
}

if (user_result == SUCCESS) { 
     if (permission_result != SUCCESS) { 
         reply.WriteErrors("error reading permissions"); 
         reply.Done(); 
         return; 
     } 
     reply.WriteErrors(""); 
} else { 
     reply.WriteErrors(user_result); 
} 
reply.Done();

if (user_result != SUCCESS) { 
 reply.WriteErrors(user_result); 
 reply.Done(); 
 return; 
} 
if (permission_result != SUCCESS) { 
 reply.WriteErrors(permission_result); 
 reply.Done(); 
 return; 
} 
reply.WriteErrors(""); 
reply.Done();

if line.split(':')[0].strip() == "root":

username = line.split(':')[0].strip() 
if username == "root":

if (request.user.id == document.owner_id) { 
 // user can edit this document... 
}

if (request.user.id != document.owner_id) { 
 // document is read-only... 
}

final boolean user_owns_document = (request.user.id == document.owner_id); 
if (user_owns_document) { 
 // user can edit this document... 
} 
... 
if (!user_owns_document) { 
 // document is read-only... 
}

if (!(file_exists && !is_protected)) Error("Sorry, could not read file.");

if (!file_exists || is_protected) Error("Sorry, could not read file.");

class LargeClass { 
 string str_; 
 void Method1() { 
 str_ = ...; 
 Method2(); 
 } 
 void Method2() { 
 // Uses str_ 
 } 
 // Lots of other methods that don't use str_ ... 
};

class LargeClass { 
 void Method1() { 
 string str = ...; 
 Method2(str); 
 } 
 void Method2(string str) { 
 // Uses str 
 } 
 // Now other methods can't see str. 
};

static const int NUM_THREADS = 10;