IConfig

The simplest interface for configuration.

This doesn't care about how data is loaded, stored, or saved. It simply provides a bare-bones interface to accessing data, without needing to worry about the nitty-gritty stuff.

interface IConfig (

) if (

is(T == struct) ||

is(T == class)

) {

void load();

void save();

T value [@property getter];

T value [@property setter];

WasExceptionThrown edit(void delegate(scope ref T value) editFunc, RollbackOnFailure rollback, SaveOnSuccess save);

void editAndSave(void delegate(scope ref T value) editFunc);

void editAndSaveNoRollback(void delegate(scope ref T value) editFunc);

void editNoRollback(void delegate(scope ref T value) editFunc);

}

Members

Functions

edit WasExceptionThrown edit(void delegate(scope ref T value) editFunc, RollbackOnFailure rollback, SaveOnSuccess save): Edit the value of this configuration using the provided editFunc, optionally saving if no exceptions are thrown, and optionally rolling back any changes in the case an exception is thrown.
editAndSave void editAndSave(void delegate(scope ref T value) editFunc): Exactly the same as edit, except with the save parameter set to yes.
editAndSaveNoRollback void editAndSaveNoRollback(void delegate(scope ref T value) editFunc): Exactly the same as edit, except with the save parameter set to yes, and rollback set to no.
editNoRollback void editNoRollback(void delegate(scope ref T value) editFunc): Exactly the same as edit, except with the rollback paramter set to no.
load void load(): Loads the configuration. This should overwrite any unsaved changes.
save void save(): Saves the configuration.

Properties

value T value [@property getter]
value T value [@property setter]: Sets the configuration's value.

Examples

// This is mostly a unittest for testing, not as an example, but may as well show it as an example anyway.
static struct Conf
{
    string str;
    int num;
}

auto config = new InMemoryConfig!Conf();

// Default: Rollback on failure, don't save on success.
// First `edit` fails, so no data should be commited.
// Second `edit` passes, so data is edited.
// Test to ensure only the second `edit` committed changes.
assert(config.edit((scope ref v) { v.str = "Hello"; v.num = 420; throw new Exception(""); }) == WasExceptionThrown.yes);
assert(config.edit((scope ref v) { v.num = 21; })                                            == WasExceptionThrown.no);
assert(config.value == Conf(null, 21));

// Reset value, check that we didn't actually call `save` yet.
config.load();
assert(config.value == Conf.init);

// Test editAndSave. Save on success, rollback on failure.
// No longer need to test rollback's pass case, as that's now proven to work.
config.editAndSave((scope ref v) { v.str = "Lalafell"; });
config.value = Conf.init;
config.load();
assert(config.value.str == "Lalafell");

// Reset value
config.value = Conf.init;
config.save();

// Test editNoRollback, and then we'll have tested the pass & fail cases for saving and rollbacks.
config.editNoRollback((scope ref v) { v.str = "Grubby"; throw new Exception(""); });
assert(config.value.str == "Grubby", config.value.str);

IConfig

Members

Functions

Properties

Examples

Meta

Source