raisch/utils

Generally useful utilities I tend to use in most of my projects.

utils

Generally useful utilities I tend to use in most of my projects.

This module is a drop-in replacement for node's util module as it includes all of its functions plus several pre-required modules, and a few generally useful custom functions.

Provides

Preloaded standard node modules:

• assert
• buffer
• events
• EventEmitter (alias,shortcut)
• fs
• path
• stream
• url

Note: There is no overhead loading node's intrinsic modules, so why not?

Pre-required modules:

• dateformat
• lodash
• stringify

Custom functions (see below):

• defineCustomError
• debug
• unload

As well as these functions from node's standard util module:

• debuglog
• format
• inherits
• inspect

Lodash

Lodash is extended with:

• isNonEmptyString(obj)

  • shorthand for _.isString(obj) && !_.isEmpty(obj)

• isNonEmptyArray(obj)

  • shorthand for _.isArray(obj) && !_.isEmpty(obj)

• isNonEmptyObject(obj)

  • shorthand for _.isPlainObject(obj) && !_.isEmpty(obj)

• setProps(target,...list) - sets properties from props on target, as in:

  • for each props in list
    • for each key in props
      • delete target[key]
      • target['_'+key] = props[key]
      • adds new 'key' getter and setter to target
  • return target

For example:

const defaults={ 
  b: false 
};

class Foo {
  constructor(opts) {
    _.setProps(this,defaults,opts);
  }
}

let f = new Foo({ a:1, isFoo:true });

f.a     // returns 1
f.a=32
f.a     // returns 32

stringify(f) // returns '{"_b":false,"_a":32,"_isFoo":true}'

Custom Functions

• defineCustomError(name, fmt=defineCustomError.FORMAT)

  • Factory function used to create new error classes
    • defineCustomError.FORMAT - default output format: ${msg}\n\t${stack}

• debug(...args)

  • Provides simple debugging output
    • args are the same as util.format
    • debug.DEBUGGING if true, debug messages are printed to console.log
    • debug.DATEMASK - default date format: hhMMss.l
    • see dateformat

• unload(path)

  • Allows required modules to be reloaded - EXPERIMENTAL