<N, E, T extends Kind = "directed">(
mutable: MutableGraph<N, E, T>,
f: (data: E) => Option.Option<E>
): voidFilters and optionally transforms edges in a mutable graph using a predicate function. Edges that return Option.none are removed from the graph.
Example (Filtering and mapping edges)
import { Graph, Option } from "effect"
const graph = Graph.directed<string, number>((mutable) => {
const a = Graph.addNode(mutable, "A")
const b = Graph.addNode(mutable, "B")
const c = Graph.addNode(mutable, "C")
Graph.addEdge(mutable, a, b, 5)
Graph.addEdge(mutable, b, c, 15)
Graph.addEdge(mutable, c, a, 25)
// Keep only edges with weight >= 10 and double their weight
Graph.filterMapEdges(
mutable,
(data) => data >= 10 ? Option.some(data * 2) : Option.none()
)
})
console.log(Graph.edgeCount(graph)) // 2 (edges with weight 5 removed)transforming
Source effect/Graph.ts:122526 lines
export const const filterMapEdges: <
N,
E,
T extends Kind = "directed"
>(
mutable: MutableGraph<N, E, T>,
f: (data: E) => Option.Option<E>
) => void
Filters and optionally transforms edges in a mutable graph using a predicate function.
Edges that return Option.none are removed from the graph.
Example (Filtering and mapping edges)
import { Graph, Option } from "effect"
const graph = Graph.directed<string, number>((mutable) => {
const a = Graph.addNode(mutable, "A")
const b = Graph.addNode(mutable, "B")
const c = Graph.addNode(mutable, "C")
Graph.addEdge(mutable, a, b, 5)
Graph.addEdge(mutable, b, c, 15)
Graph.addEdge(mutable, c, a, 25)
// Keep only edges with weight >= 10 and double their weight
Graph.filterMapEdges(
mutable,
(data) => data >= 10 ? Option.some(data * 2) : Option.none()
)
})
console.log(Graph.edgeCount(graph)) // 2 (edges with weight 5 removed)
filterMapEdges = <function (type parameter) N in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidN, function (type parameter) E in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidE, function (type parameter) T in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidT extends type Kind = "directed" | "undirected"Graph type for distinguishing directed and undirected graphs.
When to use
Use when writing graph-polymorphic types or helpers that need to preserve
whether a graph is directed or undirected.
Kind = "directed">(
mutable: MutableGraph<N, E, T>(parameter) mutable: {
type: T;
mutable: true;
nodes: Map<NodeIndex, N>;
edges: Map<EdgeIndex, Edge<E>>;
adjacency: Map<NodeIndex, Array<EdgeIndex>>;
reverseAdjacency: Map<NodeIndex, Array<EdgeIndex>>;
nextNodeIndex: NodeIndex;
nextEdgeIndex: EdgeIndex;
acyclic: Option.Option<boolean>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
interface MutableGraph<out N, out E, T extends Kind = "directed">Mutable graph interface.
When to use
Use when adding, removing, or updating nodes and edges inside a graph
mutation scope.
MutableGraph<function (type parameter) N in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidN, function (type parameter) E in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidE, function (type parameter) T in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidT>,
f: (data: E) => Option.Option<E>f: (data: Edata: function (type parameter) E in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidE) => import OptionOption.type Option<A> = Option.None<A> | Option.Some<A>The Option data type represents optional values. An Option<A> is either
Some<A>, containing a value of type A, or None, representing absence.
When to use
Use to represent initial values that may not yet exist
- Returning from partial functions (not defined for all inputs)
- Managing optional fields in data structures
Namespace containing utility types for Option.
When to use
Use to access type-level helpers associated with Option.
Option<function (type parameter) E in <N, E, T extends Kind = "directed">(mutable: MutableGraph<N, E, T>, f: (data: E) => Option.Option<E>): voidE>
): void => {
const const edgesToRemove: Array<EdgeIndex>edgesToRemove: interface Array<T>Array<type EdgeIndex = numberEdge index for edge identification using plain numbers.
When to use
Use when you need to keep the identifier for a graph edge so you can later
read, update, remove, or compare that edge.
Gotchas
An EdgeIndex is an identifier, not an array offset. Removed edge
identifiers are not reused.
EdgeIndex> = []
// First pass: identify edges to remove and transform data for edges to keep
for (const [const index: numberindex, const edgeData: Edge<E>const edgeData: {
source: number;
target: number;
data: E;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
mutable: MutableGraph<N, E, T>(parameter) mutable: {
type: T;
mutable: true;
nodes: Map<NodeIndex, N>;
edges: Map<EdgeIndex, Edge<E>>;
adjacency: Map<NodeIndex, Array<EdgeIndex>>;
reverseAdjacency: Map<NodeIndex, Array<EdgeIndex>>;
nextNodeIndex: NodeIndex;
nextEdgeIndex: EdgeIndex;
acyclic: Option.Option<boolean>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
Proto<N, E>.edges: Map<EdgeIndex, Edge<E>>edges) {
const const result: Option.Option<E>result = f: (data: E) => Option.Option<E>f(const edgeData: Edge<E>const edgeData: {
source: number;
target: number;
data: E;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
import OptionOption.const isSome: <A>(
self: Option<A>
) => self is Some<A>
Checks whether an Option contains a value (Some).
When to use
Use when you need to branch on a present Option before accessing .value.
Details
- Acts as a type guard, narrowing to
Some<A>
Example (Checking for Some)
import { Option } from "effect"
console.log(Option.isSome(Option.some(1)))
// Output: true
console.log(Option.isSome(Option.none()))
// Output: false
isSome(const result: Option.Option<E>result)) {
// Transform edge data
mutable: MutableGraph<N, E, T>(parameter) mutable: {
type: T;
mutable: true;
nodes: Map<NodeIndex, N>;
edges: Map<EdgeIndex, Edge<E>>;
adjacency: Map<NodeIndex, Array<EdgeIndex>>;
reverseAdjacency: Map<NodeIndex, Array<EdgeIndex>>;
nextNodeIndex: NodeIndex;
nextEdgeIndex: EdgeIndex;
acyclic: Option.Option<boolean>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
Proto<N, E>.edges: Map<EdgeIndex, Edge<E>>edges.Map<number, Edge<E>>.set(key: number, value: Edge<E>): Map<number, Edge<E>>Adds a new element with a specified key and value to the Map. If an element with the same key already exists, the element will be updated.
set(const index: numberindex, {
...const edgeData: Edge<E>const edgeData: {
source: number;
target: number;
data: E;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
data: Edata: const result: Option.Some<E>const result: {
_tag: "Some";
_op: "Some";
value: A;
valueOrUndefined: A;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
Some<E>.value: Evalue
})
} else {
// Mark for removal
const edgesToRemove: Array<EdgeIndex>edgesToRemove.Array<number>.push(...items: number[]): numberAppends new elements to the end of an array, and returns the new length of the array.
push(const index: numberindex)
}
}
// Second pass: remove filtered out edges
for (const const edgeIndex: numberedgeIndex of const edgesToRemove: Array<EdgeIndex>edgesToRemove) {
const removeEdge: <
N,
E,
T extends Kind = "directed"
>(
mutable: MutableGraph<N, E, T>,
edgeIndex: EdgeIndex
) => void
Removes an edge from a mutable graph.
Example (Removing an edge)
import { Graph } from "effect"
const result = Graph.mutate(Graph.directed<string, number>(), (mutable) => {
const nodeA = Graph.addNode(mutable, "Node A")
const nodeB = Graph.addNode(mutable, "Node B")
const edge = Graph.addEdge(mutable, nodeA, nodeB, 42)
// Remove the edge
Graph.removeEdge(mutable, edge)
})
removeEdge(mutable: MutableGraph<N, E, T>(parameter) mutable: {
type: T;
mutable: true;
nodes: Map<NodeIndex, N>;
edges: Map<EdgeIndex, Edge<E>>;
adjacency: Map<NodeIndex, Array<EdgeIndex>>;
reverseAdjacency: Map<NodeIndex, Array<EdgeIndex>>;
nextNodeIndex: NodeIndex;
nextEdgeIndex: EdgeIndex;
acyclic: Option.Option<boolean>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
const edgeIndex: numberedgeIndex)
}
}