active.clojure.monad — de.active-group/active-clojure 0.32.0

Monad related functionality, particularly free monads.

and-finally clj/s

(and-finally m final-m)

Execute m, and always final-m, no matter if an exception occurs or not.

Bind cljs

bind-except clj/s

(bind-except m handler f)

Evaluate m, and if an exception occurs continue with (handler exception), otherwise with (f value-of-m). Note that neither the handler result is to f, nor exceptions are caught in f.

call-cc clj/s

(call-cc f)

Construct a CallCC (Accepts a function f with one argument that returns a monadic value. call-cc packages the current continuation as a function and passes it as an argument to f. If the function is called later, the continuation of that call will be discarded and instead reinstate the continuation that was in effect when the function was created.) record.

f: access via active.clojure.monad/call-cc-f

call-cc-f clj/s

(call-cc-f CallCC)

Lens for the f field from a CallCC record. See active.clojure.monad/call-cc.

call-cc? clj/s

(call-cc? thing)

Is object a CallCC record? See active.clojure.monad/call-cc.

CallCC cljs

Accepts a function f with one argument that returns a monadic value. call-cc packages the current continuation as a function and passes it as an argument to f. If the function is called later, the continuation of that call will be discarded and instead reinstate the continuation that was in effect when the function was created.

combine-monad-command-configs clj/s

(combine-monad-command-configs & mccs)

Combine a sequence of monad-command configs into one. The earlier entries have precedence.

execute-free-reader-state-exception clj/s

(execute-free-reader-state-exception command-config m & [state])

Run monadic computation in a reader-state-exception monad, turning exceptions into Clojure exceptions.

• command-config is the configuration object for running commands
• m is the computation to run
• state is an optional initial state (from a previous run)

Returns [result state].

execute-monadic-swiss-army clj/s

(execute-monadic-swiss-army command-config m & [state])

Run monadic computation in an almighty monad, turning exceptions into Clojure exceptions. See [[`run-monadic-swiss-army]].

• command-config is the configuration object for running commands
• m is the computation to run
• state is an optional initial state (from a previous run)

Returns [result state].

free-bind clj/s

(free-bind mv f)

Bind/flatMap for the free monad.

free-bind-cont clj/s

(free-bind-cont Bind)

Lens for the cont field from a Bind record. See active.clojure.monad/make-free-bind.

free-bind-monad clj/s

(free-bind-monad Bind)

Lens for the monad field from a Bind record. See active.clojure.monad/make-free-bind.

free-bind? clj/s

(free-bind? thing)

Is object a Bind record? See active.clojure.monad/make-free-bind.

get-env-component clj/s

(get-env-component name)

Retrieve a named component of a map-valued environment.

get-state-component clj/s

(get-state-component name)

Retrieve a named component of a map-valued state.

make-free-bind clj/s

(make-free-bind monad cont)

Construct a Bind record.

monad: access via active.clojure.monad/free-bind-monad cont: access via active.clojure.monad/free-bind-cont

make-monad-command-config clj/s

(make-monad-command-config run-command env state)

Construct a MonadCommandConfig (Configuration for supporting a set of monad commands.) record.

run-command: access via active.clojure.monad/monad-command-config-run-command env: access via active.clojure.monad/monad-command-config-env state: access via active.clojure.monad/monad-command-config-state

monad-command-config-env clj/s

(monad-command-config-env MonadCommandConfig)

reader-monad initial environment represented as a mergable map

monad-command-config-run-command clj/s

(monad-command-config-run-command MonadCommandConfig)

run-command :: run-any env state comp -> (| [(| exception-value? val) state] unknown-command) Where run-any is a function for running any monad command of the signature `env state comp -> (| [(| exception-value? val) state] unknown-command)

monad-command-config-state clj/s

(monad-command-config-state MonadCommandConfig)

state-monad initial state represented as a mergable map

monad-command-config? clj/s

(monad-command-config? thing)

Is object a MonadCommandConfig record? See active.clojure.monad/make-monad-command-config.

MonadCommandConfig cljs

Configuration for supporting a set of monad commands.

monadic clj/s macro

(monadic & ?stmts)

Construct a monadic computation.

The syntax is (monadic <stmt> ...) where <stmt> is one of the following:

• [<pat> <exp> ...] which creates monadic bindings
• (let <bindings>) which creates regular bindings
• anything else is just a regular expression, expected to yield a monadic value.

Example:

(monadic [first (ask "what's your first name?")
          last (ask "what's your last name?")]
         (let [s (str "Hello, " first " " last)])
         (tell s))

null-monad-command-config clj/s

(null-monad-command-config env state)

Monad command-configuration with no commands except for reader/state/exception.

put-state-component! clj/s

(put-state-component! name value)

Set a named component of a map-valued state.

reified? clj/s

(reified? m)

Checks whether a monadic command is reified.

reify-as clj/s

(reify-as m reification)

Adds reification meta data to m that helps utilities (like the mock runner for tests), to reify a composed command as something comparable (and printable), for cases where the command itself is not; e.g. it includes a bind inside. See [[reify-command]] to extract the meta data again.

reify-command clj/s

(reify-command m)

Return the reification object of m, if one was added with [[reify-as]], or m itself otherwise.

return clj/s

run-free-reader-state-exception clj/s

(run-free-reader-state-exception command-config m & [state])

Run monadic computation in a reader-state-exception monad.

• command-config is the configuration object for running commands
• m is the computation to run
• state an optional initial state (from a previous run) that is merged into the one from command-config

Returns [result state]

run-monadic-swiss-army clj/s

(run-monadic-swiss-army command-config m & [state])

Run a monadic computation in an almighty monad. Same as [[run-free-reader-state-exception]] with the addition of call-cc.

• command-config is the configuration object for running commands
• m is the computation to run
• state an optional initial state (from a previous run) that is merged into the one from command-config

Returns [result state]

run-no-commands clj/s

(run-no-commands run-any env state m)

For use in make-monad-command-config when there are no commands.

sequ clj/s

(sequ ms)

Evaluate each action in the sequence from left to right, and collect the results.

sequ_ clj/s

(sequ_ ms)

Evaluate each action in the sequence from left to right, and ignore the results.

throw-illegal-argument-exception clj/s

(throw-illegal-argument-exception msg)

unknown-command clj/s

Marker that command functions can return to signal they don't recognize a command.

update-state-component! clj/s

(update-state-component! name f & args)

Calls f with the current value of the component and puts back return value as the new component.

with-env-component clj/s

(with-env-component key f m)

Transform a keyed component of a map-valued environment.