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what is namespace

namespace is a indicator for file . you can use specific file with specific namespace . namespace keyword is namespace

  • namespace live top level in the file . (first declare)
  • case-insensitive
  • sub directory with \ backslash

why use namespace

  • escape name collision with others file/folder/code
  • ability to use large file name with alias as very shortyly.
namespace User\Info;

class profile {
  function user() {
  echo("function name isn't case-sensitive");


how access namespace

  • access by use keyword
  • alias wirh as keyword
use User\Info;
use User\Info as client;
class Test{