haxetink / tink_querystring

Macro powered query string parsing and composition.
The Unlicense
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Tinkerbell Querystringmanglingthing

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This library provides the means to parse and build query strings - or similar structures - into or from complex Haxe objects in a type-safe reflection-free way.

Parsing

Simple Parsing

typedef Post = {
  title:String, 
  body:String,
  tags:Array<String>,
}

//relying on expected type:
var post:Post = tink.QueryString.parse('title=Example+Post&body=This+is+an+example&tags[0]=foo&tags[1]=bar');
trace(post);//{ title: 'Example Post', body: 'This is an example', tags: ['foo', 'bar'] }

//specifying the type
trace(tink.QueryString.parse(('title=Example+Post' : Post)));//Failure("Error#422: missing field body")
trace(tink.QueryString.parse(('title=Example+Post&body=whatever' : Post)));//Success({ title: 'Example Post', body: 'whatever', tags: [] })

Note that for the second usage the result is an Outcome, while for the first it is either a value of the expected type, or it throws an exception.

Parser Details

The tink.QueryString.parse macro is really just a helper for generating a tink.querystring.Parser. Note that for a single type only one parser is generated in the whole build. The generated parser is a subclass of this class:

class ParserBase<Input, Value, Result> {
  public function parse(input:Input):Result;  
  public function tryParse(input:Input):Outcome<Result, Error>;
}

To fully specify a parser type, you would use Parser<Input->Value->Result>, where Value is the type of the individual values found in the input. Much of the time you will not need this level of flexibility. So you can also leave a few things to the default: Parser<Value->Result> is a shorthand for Parser<tink.querystring.Pairs<Value>->Value->Result> and Parser<Result> is a shorthand for Parser<tink.url.Portion->Result>.

So in the above example above, we could explicitly do everything by hand like so:

var parser = tink.querystring.Parser<tink.querystring.Pairs<tink.url.Portion>->Portion->Post>();
parser.parse('title=Example+Post&body=This+is+an+example&tags[0]=foo&tags[1]=bar');

Building

Simple Building

Building querystrings is even simpler (since there's no error handling to be taken care of and the structure of the data is already well defined by the type of the data):

trace(tink.QueryString.build({ hello:'world', blabla: [1,2,3] }));//blabla[0]=1&blabla[1]=2&blabla[2]=3&hello=world

Builder Details

... to be documented