Add documentation for JSON AST

[Hexi1997]

Issue to be solved

Add doc for cadence-parser

Suggested Solution

No response

[turbolent]

Could you please describe what kind of documentation you need for the package?

You can see an example usage in the tests: https://github.com/onflow/cadence/blob/master/npm-packages/cadence-parser/tests/index.test.ts#L5-L7

[Hexi1997]

Could you please describe what kind of documentation you need for the package?

You can see an example usage in the tests: https://github.com/onflow/cadence/blob/master/npm-packages/cadence-parser/tests/index.test.ts#L5-L7

ok, my statement may not be very clear, I mean a doc like https://solidity-ast.netlify.app/

Perhaps the type of ast is more accurate!

[turbolent]

I see, thanks for clarifying. We do not have documentation for the JSON encoding of the AST element types yet, but you can maybe just look at the Go type definitions for now, they should be fairly self-explanatory.

You can find all AST element type definitions in the runtime/ast package: https://github.com/onflow/cadence/tree/master/runtime/ast. For example, the binary expression element type is defined here:

cadence/runtime/ast/expression.go

Lines 1204 to 1208 in bd4d65b

	type BinaryExpression struct {
	Left Expression
	Right Expression
	Operation Operation
	}

All element types have a MarshalJSON function that implements how the element is encoded to JSON, e.g.:

cadence/runtime/ast/expression.go

Lines 1292 to 1303 in bd4d65b

	func (e *BinaryExpression) MarshalJSON() ([]byte, error) {
	type Alias BinaryExpression
	return json.Marshal(&struct {
	*Alias
	Type string
	Range
	}{
	Type: "BinaryExpression",
	Range: NewUnmeteredRangeFromPositioned(e),
	Alias: (*Alias)(e),
	})
	}

[turbolent]

In addition, we have an AST explorer tool that lets you write Cadence code and inspect the AST: https://github.com/onflow/cadence/tree/master/tools/astexplorer