AST.json

{
  "items": [
    {
      "fn": {
        "attrs": [
          {
            "style": "outer",
            "path": {
              "segments": [
                {
                  "ident": "no_mangle"
                }
              ]
            }
          }
        ],
        "vis": "pub",
        "abi": {},
        "ident": "sum",
        "inputs": [
          {
            "typed": {
              "pat": {
                "ident": {
                  "ident": "x"
                }
              },
              "ty": {
                "path": {
                  "segments": [
                    {
                      "ident": "u64"
                    }
                  ]
                }
              }
            }
          },
          {
            "typed": {
              "pat": {
                "ident": {
                  "ident": "y"
                }
              },
              "ty": {
                "path": {
                  "segments": [
                    {
                      "ident": "u64"
                    }
                  ]
                }
              }
            }
          }
        ],
        "output": {
          "path": {
            "segments": [
              {
                "ident": "u64"
              }
            ]
          }
        },
        "stmts": [
          {
            "expr": {
              "binary": {
                "left": {
                  "path": {
                    "segments": [
                      {
                        "ident": "x"
                      }
                    ]
                  }
                },
                "op": "%",
                "right": {
                  "path": {
                    "segments": [
                      {
                        "ident": "y"
                      }
                    ]
                  }
                }
              }
            }
          }
        ]
      }
    },
    {
      "fn": {
        "attrs": [
          {
            "style": "outer",
            "path": {
              "segments": [
                {
                  "ident": "no_mangle"
                }
              ]
            }
          }
        ],
        "vis": "pub",
        "abi": {},
        "ident": "sum1",
        "inputs": [
          {
            "typed": {
              "pat": {
                "ident": {
                  "ident": "x"
                }
              },
              "ty": {
                "path": {
                  "segments": [
                    {
                      "ident": "f64"
                    }
                  ]
                }
              }
            }
          },
          {
            "typed": {
              "pat": {
                "ident": {
                  "ident": "y"
                }
              },
              "ty": {
                "path": {
                  "segments": [
                    {
                      "ident": "f64"
                    }
                  ]
                }
              }
            }
          }
        ],
        "output": {
          "tuple": {
            "elems": [
              {
                "path": {
                  "segments": [
                    {
                      "ident": "f64"
                    }
                  ]
                }
              },
              {
                "path": {
                  "segments": [
                    {
                      "ident": "f64"
                    }
                  ]
                }
              },
              {
                "path": {
                  "segments": [
                    {
                      "ident": "f64"
                    }
                  ]
                }
              }
            ]
          }
        },
        "stmts": [
          {
            "expr": {
              "tuple": {
                "elems": [
                  {
                    "path": {
                      "segments": [
                        {
                          "ident": "x"
                        }
                      ]
                    }
                  },
                  {
                    "path": {
                      "segments": [
                        {
                          "ident": "y"
                        }
                      ]
                    }
                  },
                  {
                    "binary": {
                      "left": {
                        "binary": {
                          "left": {
                            "path": {
                              "segments": [
                                {
                                  "ident": "x"
                                }
                              ]
                            }
                          },
                          "op": "+",
                          "right": {
                            "path": {
                              "segments": [
                                {
                                  "ident": "y"
                                }
                              ]
                            }
                          }
                        }
                      },
                      "op": "+",
                      "right": {
                        "path": {
                          "segments": [
                            {
                              "ident": "x"
                            }
                          ]
                        }
                      }
                    }
                  }
                ]
              }
            }
          }
        ]
      }
    },
    {
      "fn": {
        "ident": "main",
        "inputs": [],
        "output": null,
        "stmts": []
      }
    }
  ]
}

go-struct

// generated using https://mholt.github.io/json-to-go/ 

type AutoGenerated struct {
	Items []struct {
		Fn struct {
			Attrs []struct {
				Style string `json:"style"`
				Path  struct {
					Segments []struct {
						Ident string `json:"ident"`
					} `json:"segments"`
				} `json:"path"`
			} `json:"attrs"`
			Vis string `json:"vis"`
			Abi struct {
			} `json:"abi"`
			Ident  string `json:"ident"`
			Inputs []struct {
				Typed struct {
					Pat struct {
						Ident struct {
							Ident string `json:"ident"`
						} `json:"ident"`
					} `json:"pat"`
					Ty struct {
						Path struct {
							Segments []struct {
								Ident string `json:"ident"`
							} `json:"segments"`
						} `json:"path"`
					} `json:"ty"`
				} `json:"typed"`
			} `json:"inputs"`
			Output struct {
				Path struct {
					Segments []struct {
						Ident string `json:"ident"`
					} `json:"segments"`
				} `json:"path"`
			} `json:"output"`
			Stmts []struct {
				Expr struct {
					Binary struct {
						Left struct {
							Path struct {
								Segments []struct {
									Ident string `json:"ident"`
								} `json:"segments"`
							} `json:"path"`
						} `json:"left"`
						Op    string `json:"op"`
						Right struct {
							Path struct {
								Segments []struct {
									Ident string `json:"ident"`
								} `json:"segments"`
							} `json:"path"`
						} `json:"right"`
					} `json:"binary"`
				} `json:"expr"`
			} `json:"stmts"`
		} `json:"fn,omitempty"`
		Fn struct {
			Ident  string        `json:"ident"`
			Inputs []interface{} `json:"inputs"`
			Output interface{}   `json:"output"`
			Stmts  []interface{} `json:"stmts"`
		} `json:"fn,omitempty"`
	} `json:"items"`
}

main.rs

#[no_mangle]
pub extern fn sum(x:u64, y:u64) -> u64 {
  x % y 
}

#[no_mangle]
pub extern fn sum1(x:f64, y:f64) -> (f64,f64,f64) {
  (x, y, x + y + x)
}

fn main(){
}