= WebAssembly abstract address
{c}
A \b[WebAssembly abstract address] identifies an allocated runtime entity in the appropriate component of the <WebAssembly store>. Its kind distinguishes a function, memory, table or other entity. It differs from a module-local index and from an offset into <WebAssembly linear memory>.<WebAssembly Core Specification by the W3C WebAssembly Community Group>[Execution, Runtime Structure: Addresses and Module Instances]{ref}
For an original lookup example, let the store's memory at address 0 contain bytes `10,11,12`, and its memory at address 1 contain `20,21,22`. A <WebAssembly module instance> maps local memory indices `0,1` to store addresses `1,0`. Accessing its local memory index 0 at byte offset 2 therefore gives 22; local memory index 1 at the same offset gives 12.
The numerical labels need their context. A memory address 1 and a function address 1 select different store components. Byte offset 1 instead selects a location within an already selected memory. Thus writing down the integer 1 alone does not specify which of these references is intended.
The example uses invented store indices, not host-machine pointers observed from an engine. The specification uses abstract addresses to describe how runtime references resolve. <WebAssembly module> declarations supply local indices, instantiation establishes their runtime mappings, and memory instructions apply offsets within the selected object.<WebAssembly Core Specification by the W3C WebAssembly Community Group>[Runtime Structure: Store, Addresses and Module Instances]{ref}
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