# Overview
The purpose of the hclquery package is simple; given a hcl body and a query
string, it executes the query against the body and returns back a list of
blocks that satisfies the query.
# The Query
### Grammer
```
Expr ::= Segment ( '/' Segment )*
Segment ::= Ident
| Ident '{' Predicate '}'
| Ident '{' Predicate '}' '[' NUM ']'
| Block
| Block '{' Predicate '}'
Block ::= Ident '[' NUM ']'
| Ident ':' Ident
Predicate ::= Ident
| Ident '=' Literal
Literal ::= ''' CHARACTERS '''
| '"' CHARACTERS '"'
```
### Precedence
1. `=`
2. `/`, `:`, `[]` and `{}`
### Associativity
- `/`, `:`, `[]` and `{}` are left-associative.
- `=` is right-associative.
### Examples
`terraform`
find a block of type `terraform`.
```
terraform {
...
}
```
`terraform/required_providers`
find a block of type `provider` that is nested inside a block of type `terraform`.
```
terraform {
...
required_providers {
aws = {
source = "hashicorp/aws"
version = ">= 5.11.0"
}
}
...
}
```
`terraform/backend:s3`
find a block of type `backend` and label `s3` that is nested inside a block of type `terraform`
```
terraform {
backend "s3" {
...
}
...
}
```
`terraform/backend:s3{region}`
find a block of type `backend` with a label `s3` and has an attribute called `region`.
```
terraform {
backend "s3" {
...
region = "eu-west-2"
...
}
...
}
```
`terraform/backend:s3{region='eu-west-2'}`
find a block of type `backend` with a label `s3` and has an attribute called `region` with a value of `eu-west-2`
```
terraform {
backend "s3" {
...
region = "eu-west-2"
...
}
...
}
```