---
name: exists
status: documented
runtime: pp
source: src/runtime/pp/aggregate.rs
---
```{index} single: exists; Perl built-in (pp runtime)
```

# exists

## Synopsis

```perl
if (exists $hash{$key})   { ... }
if (exists $array[$idx])  { ... }
if (exists $stash{$name}) { ... }   # stash symbol lookup
```

## Description

Tests whether a hash key or array index is present in the container.

Pops a key and a container (hash or array) from the stack. For
hashes, checks whether the key is present (even if the associated
value is `undef`). For arrays, checks whether the index is within
bounds and the element has not been deleted. Pushes 1 (true) or
0 (false).

When the container is a stash (package symbol table accessed via
`%{"Package::"}`), checks for the existence of any symbol type
(scalar, array, hash, or code) with the given name.

## See also

defined, delete, keys