loop through slices and amend into a 2D array

I have 17 (len(inputStartSlice)) slices of indexes that'll make a series of string slices. Currently, my code is only producing a single slice of strings (a single input, as I hardcode the positions, seen below) when I have 17 that I need to loop through into a single, 2D array of strings.

var inputSlices []string
var inputStartSlice []int
var inputEndSlice []int
var input []string
var inputs [][]string


for v, line := range inputSlices {
  if strings.Contains(line, "{") {
    inputStartSlice = append(inputStartSlice, v)
  }
  if strings.Contains(line, "}") {
    inputEndSlice = append(inputEndSlice, v+1)
  }
}

input = inputSlice[inputStartSlice[3]:inputEndSlice[3]]

inputs = append(inputs, input)
fmt.Println(inouts)

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Is there a better way to go about doing this? I'm sure there is, if anybody can help me understand better approaches or elaborate on how I can solve where I'm currently stuck..

I've rewritten your code in a more idiomatic way. Check the comments for explanations. This code works, but as mpx suggested, for processing any custom format you have to write a tokenizer and a lexer to be sure that everything is parsed correctly and every possible syntax error is handled.

package main
import (
"fmt"
"log"
"strings"
"golang.org/x/exp/slices"
)
func main() {
var codeSlices = []string{
"# INPUTS",
"",
"input CreateUserInput {",
"  username: String!",
"  email: String!",
"  password: String!",
"}",
"",
"input AuthUserInput {",
"  user: String!",
"  password: String!",
"  code: String",
"}",
"",
"input RefreshTokensInput{",
"  refreshToken: String!",
"}",
"",
"input VerifyEmailInput {",
"  token: String!",
"}",
"",
"# OBJECTS",
"",
}
//Check for boundaries
inputStart := slices.Index(codeSlices, "# INPUTS") //Use built-in functions for the search
if inputStart == -1 {
log.Fatal("# INPUTS not found")
}
objectStart := slices.Index(codeSlices, "# OBJECTS")
if objectStart == -1 {
log.Fatal("# OBJECTS not found")
}
var inputStartSlice []int
var inputEndSlice []int
//No need to copy your codeSlices to inputSlice, just go from inputs to objects, this is faster.
for i := inputStart + 2; i < objectStart-1; i++ {
if strings.HasSuffix(codeSlices[i], "{") { //HasSuffix is better here, since the { must be the last char
inputStartSlice = append(inputStartSlice, i)
continue //No need to check for closing bracket, so we can continue to skip another check
}
if codeSlices[i] == "}" { //Direct equality is faster than Contains
inputEndSlice = append(inputEndSlice, i+1)
}
}
//Check to every open bracket have a closing one
if len(inputStartSlice) != len(inputEndSlice) {
log.Fatal("len(inputStartSlice) != len(inputEndSlice)")
}
//Concating final results
var inputs [][]string
for i := range inputStartSlice {
inputs = append(inputs, codeSlices[inputStartSlice[i]:inputEndSlice[i]])
}
fmt.Println(inputs)
}

You can achieve the same without using extra variables

package main

import (
	"fmt"
	"log"
	"strings"

	"golang.org/x/exp/slices"
)

func main() {

	var codeSlices = []string{
		"# INPUTS",
		"",
		"input CreateUserInput {",
		"  username: String!",
		"  email: String!",
		"  password: String!",
		"}",
		"",
		"input AuthUserInput {",
		"  user: String!",
		"  password: String!",
		"  code: String",
		"}",
		"",
		"input RefreshTokensInput{",
		"  refreshToken: String!",
		"}",
		"",
		"input VerifyEmailInput {",
		"  token: String!",
		"}",
		"",
		"# OBJECTS",
		"",
	}

	//Check for boundaries
	inputStart := slices.Index(codeSlices, "# INPUTS") //Use built-in functions for the search
	if inputStart == -1 {
		log.Fatal("# INPUTS not found")
	}

	objectStart := slices.Index(codeSlices, "# OBJECTS")
	if objectStart == -1 {
		log.Fatal("# OBJECTS not found")
	}

	inputStart = 0
	var inputs [][]string
	for i := inputStart + 2; i < objectStart-1; i++ {
		if idx := strings.Index(codeSlices[i], "{"); idx > 0 {
			inputStart = i
			continue
		}
		if idx := slices.Index(codeSlices[inputStart:], "}"); inputStart > 0 {
			inputs = append(inputs, codeSlices[inputStart:i+idx])
			inputStart = 0
		}
	}

	if inputStart > 0 {
		log.Fatal("Mismatch inputs")
	}

	fmt.Printf("%#v\n", inputs)
}

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