View Source Loupe.Language.Ast (Loupe v0.9.0)
Extracted AST structure query.
It uses a basic syntax like
[action] [quantifier?] [schema] where [predicates]The action is any alphanumeric value. It can be used to specify what
do you aim to use the query for. It could ̀ecto for instance that you
query Ecto with, or even ets that lookup an ets table with match spec.
The quantifier is used to limit the queries result but can be ommited
defaulting to 1. It supports the following:
- Positive integer;
1,2,10etc... - Range:
10..20, it limits the query to 10 records offsetting to the 10th record all: Returns all the record matching
The schema needs to be an idenfifier (non-quoted alphanumeric) that matches
the definition's schemas/1 function.
The predicates are combination of boolean operators and operand for validation. See the module's type for every support operators but it can basically be a syntax like
# could match `get` and run query on Ecto.
get 5 User where (name = "John Doe") or (age > 18)
# count match `protobuf` to query Ecto and generate Protobufs.
protobuf all BoardGame where name like "Catan"Link to this section Summary
Types
Alpha identifier
Composed bidings from nested querying
Valid boolean operators
Literial values usable in comparison
Valid comparison operands
Parameters provided to the query
Validation composed predicates
Query quantifier to limit the query result count
Range from one value to another
Reserved keywords
Link to this section Types
@type alpha_identifier() :: charlist()
Alpha identifier
@type binding() :: {:binding, [binary()]}
Composed bidings from nested querying
@type boolean_operator() :: :or | :and
Valid boolean operators
@type literal() :: {:float, float()} | {:int, integer()} | {:string, binary()} | {:sigil, binary()} | {:identifier, binary()}
Literial values usable in comparison
@type operand() :: := | :> | :>= | :< | :<= | :like | :in
Valid comparison operands
@type parameters() :: map()
Parameters provided to the query
@type predicate() :: {boolean_operator(), predicate(), predicate()} | {operand(), binding(), literal()} | {:not, {operand(), binding(), literal()}} | nil
Validation composed predicates
Query quantifier to limit the query result count
Range from one value to another
@type reserved_keyword() :: :empty
Reserved keywords
@type t() :: %Loupe.Language.Ast{ action: binary(), external_identifiers: external_identifiers(), parameters: parameters(), predicates: predicate(), quantifier: quantifier(), schema: binary() }
Link to this section Functions
Extracts bindings of an AST
@spec new( alpha_identifier(), alpha_identifier(), quantifier(), predicate(), object() | nil ) :: t()
Instanciates the AST
@spec unwrap_literal(literal() | object(), external_identifiers()) :: {any(), external_identifiers()}
Unwraps literal