Server IP : 108.163.255.210 / Your IP : 18.226.28.97 Web Server : Apache System : Linux blossom.urlnameserver.com 3.10.0-1160.80.1.el7.x86_64 #1 SMP Tue Nov 8 15:48:59 UTC 2022 x86_64 User : ( 1172) PHP Version : 7.2.34 Disable Function : eval,escapeshellarg,proc_close,proc_get_status,proc_nice,proc_open,symlink,system,pcntl_exec,getrusage,chown,chgp,closelog,openlog,syslog,define_syslog_variables,php_ini_loaded_file,getservbyname,getservbyport,posix_getgid,posix_getgrgid,proc_terminate,pfsockopen,apache_child_terminate,posix_mkfifo,posix_setpgid,posix_setuid,hypot,pg_host,pos,posix_access,posix_getcwd,posix_getservbyname,myshellexec,getpid,posix_getsid,posix_isatty,posix_kill,posix_mknod,posix_setgid,posix_setsid,posix_setuid,posix_times,posix_uname,ps_fill,posix_getpwuid,global,ini_restore,zip_open,zip_read,rar_open,bzopen,bzread,bzwrite,apache_get_modules,apache_get_version,phpversionphpinfo,php_ini_scanned_files,get_current_user,disk_total_space,diskfreespace,leak,imap_list,hypo,filedump,safe_mode,getmygid,apache_getenv,apache_setenv,bzread,bzwrite,bzopen,phpini,higlight_file,dos_conv,get_cwd,er_log,cmd,e_name,vdir,get_dir,only_read,ftok,ftpexec,posix_getpwnam,mysql_list_dbs,disk_free_space,session_save_path,confirm_phpdoc_compiled,zip_entry_rea,php_u,psockopen,crack_opendict,crack_getlastmessage,crack_closedict,crack_check,fpassthru,posix_get_last_error,posix_getlogin,posix_getgroups,posix_strerror,posix_getrlimit,posix_getpgrp,posix_getgrnam,pos,dl MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : ON | Sudo : ON | Pkexec : ON Directory : /home/unilinki/public_html/indijourneys.com/node_modules/once/ |
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# once Only call a function once. ## usage ```javascript var once = require('once') function load (file, cb) { cb = once(cb) loader.load('file') loader.once('load', cb) loader.once('error', cb) } ``` Or add to the Function.prototype in a responsible way: ```javascript // only has to be done once require('once').proto() function load (file, cb) { cb = cb.once() loader.load('file') loader.once('load', cb) loader.once('error', cb) } ``` Ironically, the prototype feature makes this module twice as complicated as necessary. To check whether you function has been called, use `fn.called`. Once the function is called for the first time the return value of the original function is saved in `fn.value` and subsequent calls will continue to return this value. ```javascript var once = require('once') function load (cb) { cb = once(cb) var stream = createStream() stream.once('data', cb) stream.once('end', function () { if (!cb.called) cb(new Error('not found')) }) } ``` ## `once.strict(func)` Throw an error if the function is called twice. Some functions are expected to be called only once. Using `once` for them would potentially hide logical errors. In the example below, the `greet` function has to call the callback only once: ```javascript function greet (name, cb) { // return is missing from the if statement // when no name is passed, the callback is called twice if (!name) cb('Hello anonymous') cb('Hello ' + name) } function log (msg) { console.log(msg) } // this will print 'Hello anonymous' but the logical error will be missed greet(null, once(msg)) // once.strict will print 'Hello anonymous' and throw an error when the callback will be called the second time greet(null, once.strict(msg)) ```