Module Lwt_mvar

Instructions: Use this module in your project

In the IDE (CLion, Visual Studio Code, Xcode, etc.) you use for your DkSDK project:

Add the following to your project's dependencies/CMakeLists.txt:

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DkSDKProject_DeclareAvailable(lwt
    CONSTRAINT "= 5.6.1"
    FINDLIBS lwt lwt.unix)
DkSDKProject_MakeAvailable(lwt)

Add the Findlib::lwt library to any desired targets in src/*/CMakeLists.txt:

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target_link_libraries(YourPackage_YourLibraryName
     # ... existing libraries, if any ...
     Findlib::lwt)

Click your IDE's Build button

Not using DkSDK?

FIRST, do one or all of the following:

Run:
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```
opam install lwt.5.6.1
```

Edit your dune-project and add:

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(package
  (name YourExistingPackage)
  (depends
  ; ... existing dependenices ...
  (lwt (>= 5.6.1))))

Then run:

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dune build *.opam # if this fails, run: dune build

Edit your <package>.opam file and add:

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depends: [
  # ... existing dependencies ...
  "lwt" {>= "5.6.1"}
]

Then run:

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opam install . --deps-only

FINALLY, add the lwt library to any desired (library)and/or (executable) targets in your **/dune files:

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(library
  (name YourLibrary)
  ; ... existing library options ...
  (libraries
    ; ... existing libraries ...
    lwt))

(executable
  (name YourExecutable)
  ; ... existing executable options ...
  (libraries
    ; ... existing libraries ...
    lwt))

“Mailbox” variables implement a synchronising variable, used for communication between concurrent threads.

type ``'a t

The type of a mailbox variable. Mailbox variables are used to communicate values between threads in a synchronous way. The type parameter specifies the type of the value propagated from put to take.

valcreate :'a -> 'a t

create v creates a new mailbox variable containing value v.

valcreate_empty : ``unit-> 'a t

create () creates a new empty mailbox variable.

valput :'a t -> 'a ->``unitLwt.t

put mvar value puts a value into a mailbox variable. This value will remain in the mailbox until take is called to remove it. If the mailbox is not empty, the current thread will block until it is emptied.

valtake :'a t -> 'a Lwt.t

take mvar will take any currently available value from the mailbox variable. If no value is currently available, the current thread will block, awaiting a value to be put by another thread.

valtake_available :'a t -> 'a option

take_available mvar immediately takes the value from mvar without blocking, returning None if the mailbox is empty.

since 3.2.0

valis_empty :'a t -> bool

is_empty mvar indicates if put mvar can be called without blocking.

since 3.2.0

Module Lwt_mvar

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