Struct Block

source

pub struct Block {
    pub ident: Decorated<Ident>,
    pub labels: Vec<BlockLabel>,
    pub body: Body,
    /* private fields */
}

Expand description

Represents an HCL block which consists of a block identifier, zero or more block labels and a block body.

In HCL syntax this is represented as:

block_identifier "block_label1" "block_label2" {
  body
}

Fields§

§ident: Decorated<Ident>

The block identifier.

§labels: Vec<BlockLabel>

Zero or more block labels.

§body: Body

Represents the Block’s body.

Implementations§

source §

impl Block

source

pub fn new(ident: impl Into<Decorated<Ident>>) -> Block

Creates a new Block from an identifier.

source

pub fn builder(ident: impl Into<Decorated<Ident>>) -> BlockBuilder

Creates a new BlockBuilder to start building a new Block with the provided identifier.

source

pub fn is_labeled(&self) -> bool

Returns true if the block has labels.

§Example

use hcl_edit::{structure::Block, Ident};

let block = Block::new(Ident::new("foo"));
assert!(!block.is_labeled());

let labeled_block = Block::builder(Ident::new("foo"))
    .label("bar")
    .build();
assert!(labeled_block.is_labeled());

source

pub fn has_ident(&self, ident: &str) -> bool

Returns true if the block has the given identifier.

§Example

use hcl_edit::{structure::Block, Ident};

let block = Block::new(Ident::new("foo"));
assert!(block.has_ident("foo"));
assert!(!block.has_ident("bar"));

source

pub fn has_labels<T>(&self, labels: &[T]) -> bool
where T: AsRef<str>,

Returns true if the Block’s labels and the provided ones share a common prefix.

For example, &["foo"] will match blocks that fulfil either of these criteria:

Single "foo" label.
Multiple labels, with "foo" being in first position.

For an alternative which matches labels exactly see Block::has_exact_labels.

§Examples

use hcl_edit::{structure::Block, Ident};

let block = Block::builder(Ident::new("resource"))
    .labels(["aws_s3_bucket", "mybucket"])
    .build();

assert!(block.has_labels(&["aws_s3_bucket"]));
assert!(block.has_labels(&["aws_s3_bucket", "mybucket"]));
assert!(!block.has_labels(&["mybucket"]));

One use case for this method is to find blocks in a Body that have a common label prefix:

use hcl_edit::structure::{Attribute, Block, Body};
use hcl_edit::Ident;

let body = Body::builder()
    .attribute(Attribute::new(Ident::new("foo"), "bar"))
    .block(
        Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket1"])
    )
    .block(
        Block::builder(Ident::new("resource"))
            .labels(["aws_db_instance", "db_instance"])
    )
    .block(
        Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket2"])
    )
    .build();

let buckets: Vec<&Block> = body.get_blocks("resource")
    .filter(|block| block.has_labels(&["aws_s3_bucket"]))
    .collect();

assert_eq!(
    buckets,
    [
        &Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket1"])
            .build(),
        &Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket2"])
            .build()
    ]
);

source

pub fn has_exact_labels<T>(&self, labels: &[T]) -> bool
where T: AsRef<str>,

Returns true if the Block’s labels match the provided ones exactly.

For an alternative which matches a common label prefix see Block::has_labels.

§Examples

use hcl_edit::{structure::Block, Ident};

let block = Block::builder(Ident::new("resource"))
    .labels(["aws_s3_bucket", "mybucket"])
    .build();

assert!(!block.has_exact_labels(&["aws_s3_bucket"]));
assert!(block.has_exact_labels(&["aws_s3_bucket", "mybucket"]));

One use case for this method is to find blocks in a Body that have an exact set of labels:

use hcl_edit::structure::{Attribute, Block, Body};
use hcl_edit::Ident;

let body = Body::builder()
    .block(
        Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket1"])
    )
    .block(
        Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket2"])
    )
    .build();

let buckets: Vec<&Block> = body.get_blocks("resource")
    .filter(|block| block.has_exact_labels(&["aws_s3_bucket", "bucket1"]))
    .collect();

assert_eq!(
    buckets,
    [
        &Block::builder(Ident::new("resource"))
            .labels(["aws_s3_bucket", "bucket1"])
            .build(),
    ]
);