红色语言的并行列表分配 [英] Parallel list assignment in Red language

问题描述

我有2个列表:

alist: [a b c d]
blist: [1 2 3 4]

(实际上，它们很长).如何一次性将alist中的变量分配给blist中的相应值?因此，a变为1，b变为2，依此类推.

(In reality they are long lists). How can I assign variables in alist to corresponding values in blist in one go? Hence a becomes 1, b becomes 2 and so on.

我尝试过:

foreach i alist j blist [i: j]

但是它给出了以下错误:

But it give following error:

*** Script Error: j has no value
*** Where: foreach
*** Stack: 

我也尝试过:

i: 1
while [true] [ 
    if i > (length? alist) [break]
    alist/i: blist/i  
    i: i + 1
]

但是它也不起作用:

*** Script Error: cannot set none in path alist/i:
*** Where: set-path
*** Stack: 

alist/i和blist/i返回none(通过打印命令检查).

alist/i and blist/i return none (on checking with print command).

其他语言也有类似的问题，例如: PHP中的并行数组分配和 Java中的并行分配?.感谢您的帮助.

Similar question are there for other languages also, e.g.: Parallel array assignment in PHP and Parallel assignment in Java? . Thanks for your help.

推荐答案

简便的方法，将一个列表设置为另一个列表

easy way, set one list to the other

>> set alist blist
== [1 2 3 4]
>> a
== 1
>> b
== 2
>> c
== 3
>> d
== 4
>> alist
== [a b c d]
>> reduce alist
== [1 2 3 4]
>> get alist/1    
== 1

和繁琐的方式

>> forall alist [alist/1: blist/(index? alist) ]
>> i: 2
== 2
>> get alist/:i
== 2

这篇关于红色语言的并行列表分配的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！