Two of My Use Cases of Lazy Evaluation | /en/2018/07/lazy-evaluation/

yihui 2022-12-17 03:53:59

Two of My Use Cases of Lazy Evaluation

https://yihui.org/en/2018/07/lazy-evaluation/

1 Comment

giscus-bot 2022-12-17 03:54:00

Guest *baptiste auguie* @ 2018-08-04 22:17:32 originally posted:

thanks for the tip; I've often wanted a shortcut for system("open .") on my mac,

delayedAssign('open', {  
system('open .')  
invisible(getwd())  
})

yihui 2022-12-17 03:54:01

The problem is that it only works once (I guess you are aware of that). Once the delayed assignment is fulfilled, open will be getwd(), and it won't open the directory again if you run open in the console.

Originally posted on 2018-08-05 02:21:40

giscus-bot 2022-12-17 03:54:02

Guest *baptiste auguie* @ 2018-08-05 02:47:23 originally posted:

yes :( found out after I posted this

giscus-bot 2022-12-17 03:54:03

Guest *Michael* @ 2018-08-06 19:03:08 originally posted:

makeActiveBinding would work here:

makeActiveBinding("open", function(){  
system('open .')  
invisible(getwd())  
}, .GlobalEnv)