@circom:tree.verify

Verify a Poseidon Merkle inclusion proof against a root, using the path index and siblings produced by @circom:tree.proof.

⚗️ Experimental — available at next.evmcrispr.com.

Returns: bool

Syntax

@circom:tree.verify(root leaf index proof lean:<value> depth:<value>)

Arguments

Name	Type	Description
`root`	`number`	Merkle root
`leaf`	`number`	Leaf to prove
`index`	`number`	Path index from @circom:tree.proof (equals the leaf index for fixed-depth and complete lean trees)
`proof`	`array`	Array of sibling field elements, leaf to root
`lean:`	`bool`	`lean:true` — Semaphore v4 LeanIMT (the default when depth: is not set)
`depth:`	`number`	`depth:<n>` — zero-padded fixed-depth tree

Examples

# Check a member's inclusion proof off-chain
set $leaves [1234 5678 9012]
set $root @circom:tree.root($leaves)
set [$index $siblings] @circom:tree.proof($leaves 2)
print "Member included:" @circom:tree.verify($root 9012 $index $siblings)

Notes

index is the path index returned by @circom:tree.proof, not necessarily the leaf position (they differ for incomplete lean trees).
Fixed-depth proofs must have exactly depth siblings.

See Also

@circom:tree.proof — produces [pathIndex siblings]
@circom:tree.root — the tree conventions