later: run_now – R documentation

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run_now

Execute scheduled operations

Description

Normally, operations scheduled with later() will not execute unless/until no other R code is on the stack (i.e. at the top-level). If you need to run blocking R code for a long time and want to allow scheduled operations to run at well-defined points of your own operation, you can call run_now() at those points and any operations that are due to run will do so.

Usage

run_now(timeoutSecs = 0L, all = TRUE, loop = current_loop())

Arguments

`timeoutSecs`	Wait (block) for up to this number of seconds waiting for an operation to be ready to run. If `0`, then return immediately if there are no operations that are ready to run. If `Inf` or negative, then wait as long as it takes (if none are scheduled, then this will block forever).
`all`	If `FALSE`, `run_now()` will execute at most one scheduled operation (instead of all eligible operations). This can be useful in cases where you want to interleave scheduled operations with your own logic.
`loop`	A handle to an event loop. Defaults to the currently-active loop.

Details

If one of the callbacks throws an error, the error will not be caught, and subsequent callbacks will not be executed (until run_now() is called again, or control returns to the R prompt). You must use your own tryCatch if you want to handle errors.

Value

A logical indicating whether any callbacks were actually run.

later

Utilities for Scheduling Functions to Execute Later with Event Loops

v1.2.0

MIT + file LICENSE

Authors

Winston Chang [aut, cre], Joe Cheng [aut], RStudio [cph], Marcus Geelnard [ctb, cph] (TinyCThread library, https://tinycthread.github.io/), Evan Nemerson [ctb, cph] (TinyCThread library, https://tinycthread.github.io/)

Initial release