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diff --git a/sandbox/testAppNevena/Front/node_modules/aproba/README.md b/sandbox/testAppNevena/Front/node_modules/aproba/README.md new file mode 100644 index 00000000..0bfc594c --- /dev/null +++ b/sandbox/testAppNevena/Front/node_modules/aproba/README.md @@ -0,0 +1,94 @@ +aproba +====== + +A ridiculously light-weight function argument validator + +``` +var validate = require("aproba") + +function myfunc(a, b, c) { + // `a` must be a string, `b` a number, `c` a function + validate('SNF', arguments) // [a,b,c] is also valid +} + +myfunc('test', 23, function () {}) // ok +myfunc(123, 23, function () {}) // type error +myfunc('test', 23) // missing arg error +myfunc('test', 23, function () {}, true) // too many args error + +``` + +Valid types are: + +| type | description +| :--: | :---------- +| * | matches any type +| A | `Array.isArray` OR an `arguments` object +| S | typeof == string +| N | typeof == number +| F | typeof == function +| O | typeof == object and not type A and not type E +| B | typeof == boolean +| E | `instanceof Error` OR `null` **(special: see below)** +| Z | == `null` + +Validation failures throw one of three exception types, distinguished by a +`code` property of `EMISSINGARG`, `EINVALIDTYPE` or `ETOOMANYARGS`. + +If you pass in an invalid type then it will throw with a code of +`EUNKNOWNTYPE`. + +If an **error** argument is found and is not null then the remaining +arguments are optional. That is, if you say `ESO` then that's like using a +non-magical `E` in: `E|ESO|ZSO`. + +### But I have optional arguments?! + +You can provide more than one signature by separating them with pipes `|`. +If any signature matches the arguments then they'll be considered valid. + +So for example, say you wanted to write a signature for +`fs.createWriteStream`. The docs for it describe it thusly: + +``` +fs.createWriteStream(path[, options]) +``` + +This would be a signature of `SO|S`. That is, a string and and object, or +just a string. + +Now, if you read the full `fs` docs, you'll see that actually path can ALSO +be a buffer. And options can be a string, that is: +``` +path <String> | <Buffer> +options <String> | <Object> +``` + +To reproduce this you have to fully enumerate all of the possible +combinations and that implies a signature of `SO|SS|OO|OS|S|O`. The +awkwardness is a feature: It reminds you of the complexity you're adding to +your API when you do this sort of thing. + + +### Browser support + +This has no dependencies and should work in browsers, though you'll have +noisier stack traces. + +### Why this exists + +I wanted a very simple argument validator. It needed to do two things: + +1. Be more concise and easier to use than assertions + +2. Not encourage an infinite bikeshed of DSLs + +This is why types are specified by a single character and there's no such +thing as an optional argument. + +This is not intended to validate user data. This is specifically about +asserting the interface of your functions. + +If you need greater validation, I encourage you to write them by hand or +look elsewhere. + |