fluent assert for validation of invariants before assignment
npm install krash
javascript
var delicate = krash.unless(suspect, isDefined, 'suspect not defined')
`
particularly helpful together with your favorite library of predicates such as
lodash/Lang,
predicate,
predicates, ...note that it's easy to use a shorter alias for
, for example:
`javascript
var assert = require('krash').unless
...
var delicate = assert(suspect, isDefined, 'suspect not defined')
...
` also comes with a helper for throwing,
that helps with formating the error message: krash.now(...message)usage
example
javascript
var krash = require('krash')function fun (suspect) {
// assert the invariants:
// assign suspect to delicate if defined, otherwise throw 'suspect not defined'
var delicate = krash.unless(suspect, isDefined, 'suspect not defined')
}
// example of predicate that returns a boolean
function isDefined (val) {
return (typeof val !== 'undefined') && (val !== null)
}
fun(undefined) // throw 'suspect not defined'
`signatures
krash.unless(val: , predicate: function, ...message: string[])
* val any the value to check against the predicate and return if valid
* predicate function given val, returns a boolean
* ...message the remaining arguments are assembled by util#format
to generate the error message
* return val if predicate(val) is true
* throw if predicate(val) is falsekrash.now(...message:
)
* ...message string[] the arguments are assembled by util#format
to generate the error message
* throw