Decode JSON

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Examples in V
Decode JSON in V
by yhuang V 
// JSON is very popular nowadays, that's why JSON support is built in.
// The first argument of the json.decode function is the type to decode to. 
// The second argument is the JSON string.
// V generates code for JSON encoding and decoding. No runtime reflection is used.
// This results in much better performance.

import json

struct Foo {
	bar int
}

struct User {
	name string
	age  int

	// Use the `skip` attribute to skip certain fields
	foo Foo [skip]  

	// If the field name is different in JSON, it can be specified
	last_name string [json:lastName]  
}

data := '{ "name": "Frodo", "lastName": "Baggins", "age": 25 }'
user := json.decode(User, data) or {
	eprintln('Failed to decode json')
	return
}
println(user.name)
println(user.last_name)
println(user.age)
Last Run  :
V panic: array.get: index out of range (i == -1, a.len == 0)
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                                               | 0x55c616e9cfa1 | /code/root/v/v(+0x7ffa1) 
                                               | 0x55c616e9c853 | /code/root/v/v(+0x7f853) 
                                               | 0x55c616e820b7 | /code/root/v/v(+0x650b7) 
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                                               | 0x55c616edfd02 | /code/root/v/v(+0xc2d02) 
                                               | 0x55c616eeae44 | /code/root/v/v(+0xcde44) 
                                               | 0x7fd08f36fb97 | /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7) 
                                               | 0x55c616e1fbba | /code/root/v/v(+0x2bba)