hcl/expr/
for_expr.rs

1use super::Expression;
2use crate::Identifier;
3use serde::Deserialize;
4
5/// A for expression is a construct for constructing a collection by projecting the items from
6/// another collection.
7#[derive(Deserialize, Debug, PartialEq, Eq, Clone)]
8pub struct ForExpr {
9    /// Optional name of the variable that will be temporarily assigned the key of each element
10    /// during iteration. If the source collection is an array, it gets assigned the zero-based
11    /// array index. For an object source collection, this gets assigned the object's key.
12    pub key_var: Option<Identifier>,
13    /// The name of the variable that will be temporarily assigned the value of each element
14    /// during iteration.
15    pub value_var: Identifier,
16    /// An expression that must evaluate to a value that can be iterated.
17    pub collection_expr: Expression,
18    /// An expression that is evaluated once for each key in the source collection. If set, the
19    /// result of the `for` expression will be an object. Otherwise, the result will be an array.
20    pub key_expr: Option<Expression>,
21    /// An expression that is evaluated once for each value in the source collection.
22    pub value_expr: Expression,
23    /// Indicates whether grouping mode is enabled. In grouping mode, each value in the resulting
24    /// object is a list of all of the values that were produced against each distinct key. This is
25    /// ignored if `key_expr` is `None`.
26    pub grouping: bool,
27    /// An optional filter expression. Elements for which the condition evaluates to `true` will
28    /// be evaluated as normal, while if `false` the element will be skipped.
29    pub cond_expr: Option<Expression>,
30}
31
32impl ForExpr {
33    /// Create a new `ForExpr` with the name of the variable that will be temporarily assigned the
34    /// value of each element during iteration, an expression that must evaluate to a value that
35    /// can be iterated, and one expression that is evaluated once for each value in the source
36    /// collection.
37    pub fn new<C, V>(value_var: Identifier, collection_expr: C, value_expr: V) -> ForExpr
38    where
39        C: Into<Expression>,
40        V: Into<Expression>,
41    {
42        ForExpr {
43            key_var: None,
44            value_var,
45            collection_expr: collection_expr.into(),
46            key_expr: None,
47            value_expr: value_expr.into(),
48            grouping: false,
49            cond_expr: None,
50        }
51    }
52
53    /// Adds the iterator key variable identifier to the `for` expression and returns the modified
54    /// `ForExpr`.
55    pub fn with_key_var(mut self, key_var: Identifier) -> ForExpr {
56        self.key_var = Some(key_var);
57        self
58    }
59
60    /// Adds an expression that is evaluated once for each key in the source collection. If set,
61    /// the result of the `for` expression will be an object. Returns the modified `ForExpr`.
62    pub fn with_key_expr<T>(mut self, key_expr: T) -> ForExpr
63    where
64        T: Into<Expression>,
65    {
66        self.key_expr = Some(key_expr.into());
67        self
68    }
69
70    /// Sets the filter expression. Elements for which the condition evaluates to `true` will be
71    /// evaluated as normal, while if `false` the element will be skipped.
72    pub fn with_cond_expr<T>(mut self, cond_expr: T) -> ForExpr
73    where
74        T: Into<Expression>,
75    {
76        self.cond_expr = Some(cond_expr.into());
77        self
78    }
79
80    /// Enables or disabled grouping mode.
81    pub fn with_grouping(mut self, yes: bool) -> ForExpr {
82        self.grouping = yes;
83        self
84    }
85}
hcl/expr/for_expr.rs

hcl/expr/
for_expr.rs
