Class: SQLite3::Database::FunctionProxy
- Inherits:
-
Object
- Object
- SQLite3::Database::FunctionProxy
- Defined in:
- lib/sqlite3/database.rb
Overview
A helper class for dealing with custom functions (see #create_function, #create_aggregate, and #create_aggregate_handler). It encapsulates the opaque function object that represents the current invocation. It also provides more convenient access to the API functions that operate on the function object.
This class will almost always be instantiated indirectly, by working with the create methods mentioned above.
Instance Method Summary collapse
-
#[](key) ⇒ Object
Returns the value with the given key from the context.
-
#[]=(key, value) ⇒ Object
Sets the value with the given key in the context.
-
#count ⇒ Object
(Only available to aggregate functions.) Returns the number of rows that the aggregate has processed so far.
-
#initialize(driver, func, context = nil) ⇒ FunctionProxy
constructor
Create a new FunctionProxy that encapsulates the given
func
object. -
#result=(result) ⇒ Object
Calls #set_result to set the result of this function.
-
#set_error(error) ⇒ Object
Set the result of the function to the given error message.
-
#set_result(result, utf16 = false) ⇒ Object
Set the result of the function to the given value.
Constructor Details
#initialize(driver, func, context = nil) ⇒ FunctionProxy
Create a new FunctionProxy that encapsulates the given func
object. If context is non-nil, the functions context will be set to that. If it is non-nil, it must quack like a Hash. If it is nil, then none of the context functions will be available.
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# File 'lib/sqlite3/database.rb', line 630 def initialize(driver, func, context = nil) @driver = driver @func = func @context = context end |
Instance Method Details
#[](key) ⇒ Object
Returns the value with the given key from the context. This is only available to aggregate functions.
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# File 'lib/sqlite3/database.rb', line 663 def [](key) ensure_aggregate! @context[key] end |
#[]=(key, value) ⇒ Object
Sets the value with the given key in the context. This is only available to aggregate functions.
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# File 'lib/sqlite3/database.rb', line 670 def []=(key, value) ensure_aggregate! @context[key] = value end |
#count ⇒ Object
(Only available to aggregate functions.) Returns the number of rows that the aggregate has processed so far. This will include the current row, and so will always return at least 1.
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# File 'lib/sqlite3/database.rb', line 656 def count ensure_aggregate! @driver.aggregate_count(@func) end |
#result=(result) ⇒ Object
Calls #set_result to set the result of this function.
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# File 'lib/sqlite3/database.rb', line 637 def result=(result) set_result(result) end |
#set_error(error) ⇒ Object
Set the result of the function to the given error message. The function will then return that error.
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# File 'lib/sqlite3/database.rb', line 649 def set_error(error) @driver.result_error(@func, error.to_s, -1) end |
#set_result(result, utf16 = false) ⇒ Object
Set the result of the function to the given value. The function will then return this value.
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# File 'lib/sqlite3/database.rb', line 643 def set_result(result, utf16 = false) @driver.result_text(@func, result, utf16) end |