diff --git a/gitlab-pages/docs/reference/big_map.md b/gitlab-pages/docs/reference/big_map.md index 952275c1c..9ef541929 100644 --- a/gitlab-pages/docs/reference/big_map.md +++ b/gitlab-pages/docs/reference/big_map.md @@ -1,25 +1,36 @@ --- id: big-map-reference -title: Big Maps — Scalable Maps +title: Big_map +description: A lazily deserialized map that's intended to store large amounts of data. +hide_table_of_contents: true --- import Syntax from '@theme/Syntax'; +import SyntaxTitle from '@theme/SyntaxTitle'; -Ordinary maps are fine for contracts with a finite lifespan or a -bounded number of users. For many contracts however, the intention is -to have a map holding *many* entries, potentially millions of -them. The cost of loading those entries into the environment each time -a user executes the contract would eventually become too expensive -were it not for *big maps*. Big maps are a data structure offered by -Michelson which handles the scaling concerns for us. In LIGO, the -interface for big maps is analogous to the one used for ordinary maps. +A lazily deserialized map that's intended to store large amounts of data. -# Declaring a Map +The gast costs of deserialized maps are higher than standard maps as data is lazily deserialized. + +type big_map (key, value) + + + + +type ('key, 'value) big_map + + +type big_map ('key, 'value) + + -```pascaligo group=big_maps +The type of a big map from values of type `key` to +values of type `value` is `big_map (key, value)`. + +```pascaligo group=big_map type move is int * int type register is big_map (address, move) ``` @@ -27,57 +38,91 @@ type register is big_map (address, move) -```cameligo group=big_maps +The type of a big map from values of type `key` to values +of type `value` is `(key, value) big_map`. + +```cameligo group=big_map type move = int * int type register = (address, move) big_map ``` +The type of a big map from values of type `key` to +values of type `value` is `big_map (key, value)`. -```reasonligo group=big_maps +```reasonligo group=big_map type move = (int, int); type register = big_map (address, move); ``` + +function empty : big_map (key, value) + + +val empty : ('key, 'value) big_map + + +let empty: big_map ('key, 'value) + - -# Creating an Empty Big Map - - +Create an empty big_map. -```pascaligo group=big_maps +```pascaligo group=big_map +const empty : register = Big_map.empty +``` + +Alternatively, you can also create an empty big_map using: + +```pascaligo group=big_map const empty : register = big_map [] ``` -```cameligo group=big_maps +```cameligo group=big_map let empty : register = Big_map.empty ``` -```reasonligo group=big_maps +```reasonligo group=big_map let empty : register = Big_map.empty ``` -# Creating a Non-empty Map - + +function literal : list (key * value) -> big_map (key, value) + + +val literal : ('key * 'value) list -> ('key, 'value) big_map + + +let literal: list(('key, 'value)) => big_map('key, 'value) + +Create a non-empty big_map. -```pascaligo group=big_maps +```pascaligo group=big_map +const moves : register = + Big_map.literal ([ + ("tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx" : address) -> (1,2); + ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address) -> (0,3)]) +``` + +Alternative way of creating an empty big_map: + +```pascaligo group=big_map const moves : register = big_map [ ("tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx" : address) -> (1,2); @@ -87,7 +132,7 @@ const moves : register = -```cameligo group=big_maps +```cameligo group=big_map let moves : register = Big_map.literal [ (("tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx" : address), (1,2)); @@ -97,7 +142,7 @@ let moves : register = -```reasonligo group=big_maps +```reasonligo group=big_map let moves : register = Big_map.literal ([ ("tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx" : address, (1,2)), @@ -106,13 +151,32 @@ let moves : register = + +function find_opt : key -> big_map (key, value) -> option value + + +val find_opt : 'key -> ('key, 'value) big_map -> 'value option + + +let find_opt : ('key, big_map ('key, 'value)) => option ('value) + -# Accessing Values +Retrieve a value from a big map with the given key. + +Because the key may be missing in the big map, the result is an +*optional value*. -```pascaligo group=big_maps +```pascaligo group=big_map +const my_balance : option (move) = + Big_map.find_opt ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address, moves) +``` + +Alternatively: + +```pascaligo group=big_map const my_balance : option (move) = moves [("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address)] ``` @@ -120,7 +184,7 @@ const my_balance : option (move) = -```cameligo group=big_maps +```cameligo group=big_map let my_balance : move option = Big_map.find_opt ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address) moves ``` @@ -128,33 +192,57 @@ let my_balance : move option = -```reasonligo group=big_maps +```reasonligo group=big_map let my_balance : option (move) = Big_map.find_opt ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address, moves); ``` + +function update : key -> option value -> big_map (key, value) -> big_map (key, value) + + +val update: 'key -> 'value option -> ('key, 'value) big_map -> ('key, 'value) big_map + + +let update: ('key, option('value), big_map ('key, 'value)) => big_map ('key, 'value) + - -# Updating Big Maps - +Note: when `None` is used as a value, the value is removed from the big_map. -```pascaligo group=big_maps -function add (var m : register) : register is - block { - m [("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address)] := (4,9) - } with m - -const updated_map : register = add (moves) +```pascaligo group=big_map + Big_map.update(("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address), m, (4,9)); ``` +Alternatively: + +```pascaligo group=big_map + m [("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address)] := (4,9) +``` + +If multiple bindings need to be updated, PascaLIGO offers a *patch +instruction* for maps, similar to that for records. + +```pascaligo group=big_map +function assignments (var m : register) : register is + block { + patch m with map [ + ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address) -> (4,9); + ("tz1KqTpEZ7Yob7QbPE4Hy4Wo8fHG8LhKxZSx" : address) -> (1,2) + ] + } with m +``` + +> Note the use of the keyword `map` instead of `big_map` (which is not +> a keyword). + -```cameligo group=big_maps +```cameligo group=big_map let updated_map : register = Big_map.update ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address) (Some (4,9)) moves @@ -163,7 +251,7 @@ let updated_map : register = -```reasonligo group=big_maps +```reasonligo group=big_map let updated_map : register = Big_map.update (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address), Some ((4,9)), moves); @@ -171,14 +259,64 @@ let updated_map : register = + +function add : key -> value -> big_map (key, value) -> big_map (key, value) + + +val add : 'key -> 'value -> ('key, 'value) big_map -> ('key, 'value) big_map + + +let add: ('key, 'value, big_map('key, 'value)) => big_map('key, 'value) + + -# Removing Bindings +```pascaligo group=big_map +Big_map.add (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address), (4, 9), m) +``` + + + + +```cameligo group=big_map +let add (m : register) : register = + Big_map.add + ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address) (4,9) m +``` + + + + +```reasonligo group=big_map +let add = (m: register): register => + Big_map.add + (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN" : address), (4,9), m); +``` + + + +function remove: key -> big_map (key, value) -> big_map (key, value) + + +val remove: 'key -> ('key, 'value) big_map -> ('key, 'value) big_map + + +let remove: (key, big_map ('key, 'value)) => big_map ('key, 'value) + -```pascaligo group=big_maps +```pascaligo group=big_map + const_updated_map : register = + Big_map.remove (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address), moves) +``` + +Alternatively, the instruction `remove key from map m` removes the key +`key` from the big map `m` (note that the keyword is `map`, not +`big_map`). + +```pascaligo group=big_map function rem (var m : register) : register is block { remove ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address) from map moves @@ -190,17 +328,17 @@ const updated_map : register = rem (moves) -```cameligo group=big_maps +```cameligo group=big_map let updated_map : register = - Map.remove ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address) moves + Big_map.remove ("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address) moves ``` -```reasonligo group=big_maps +```reasonligo group=big_map let updated_map : register = - Map.remove (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address), moves) + Big_map.remove (("tz1gjaF81ZRRvdzjobyfVNsAeSC6PScjfQwN": address), moves) ```