interop/input|output: update documentation

pkg/interop/input/input.go

@@ -1,17 +1,22 @@
+/*
+Package input provides functions dealing with transaction inputs.
+*/
 package input
 
-// Package input provides function signatures that can be used inside
+// Input is an opaque data structure that can only be created by
-// smart contracts that are written in the neo-go framework.
+// transaction.GetInputs and it represents transaction's input. It's similar
-
+// to Neo .net framework's TransactionInput.
-// Input stubs the input of a NEO transaction.
 type Input struct{}
 
-// GetHash returns the hash of the given input.
+// GetHash returns the hash stored in the given input (which also is a
+// transaction ID represented as 32 byte slice containing 256 bit BE value).
+// It uses `Neo.Input.GetHash` syscall.
 func GetHash(in Input) []byte {
 	return nil
 }
 
-// GetIndex returns the index of the given input.
+// GetIndex returns the index stored in the given input (which is a
+// transaction's output number). It uses `Neo.Input.GetIndex` syscall.
 func GetIndex(in Input) int {
 	return 0
 }

pkg/interop/output/output.go

@@ -1,22 +1,28 @@
+/*
+Package output provides functions dealing with transaction outputs.
+*/
 package output
 
-// Package output provides function signatures that can be used inside
+// Output is an opaque data structure that can only be created by
-// smart contracts that are written in the neo-go framework.
+// transaction.GetOutputs and it represents transaction's output. It's similar
-
+// to Neo .net framework's TransactionOutput.
-// Output stubs the output of a NEO transaction.
 type Output struct{}
 
-// GetAssetID returns the asset id of the given output.
+// GetAssetID returns the asset ID (256 bit BE value in a 32 byte slice) of the
+// given output. It uses `Neo.Output.GetAssetId` syscall.
 func GetAssetID(out Output) []byte {
 	return nil
 }
 
-// GetValue returns the value of the given output.
+// GetValue returns the value (asset quantity) of the given output. It uses
+// `Neo.Output.GetValue` syscall.
 func GetValue(out Output) int {
 	return 0
 }
 
-// GetScriptHash returns the script hash of the given output.
+// GetScriptHash returns the script hash (receiver's address represented as
+// 20 byte slice containing 160 bit BE value) of the given output. It uses
+// `Neo.Output.GetScriptHash` syscall.
 func GetScriptHash(out Output) []byte {
 	return nil
 }