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Update syntax-list-comprehensions.md

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rfcs/syntax-list-comprehensions.md
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@ -7,13 +7,14 @@ Introduce a form of list comprehension using `n for-in-do` syntax.
List comprehensions would bring several benefits and prevent code smell.
In Lua you are encouraged to not modify tables during traversal.
When traversing a table to exclude all the odd numbers you'd be creating a large statement to get rid of them, with list comprehensions this could be shortened and cleaner
When traversing a table to exclude all the odd numbers you'd be creating a large statement to get rid of them, with list comprehensions this could be shortened and cleaner.
## Design
To solve these problems, I propose a `n for-in-do` expression form that is syntactically similar to a for statement, but lacks terminating `end`.
The `n for-in-do` expression must match ``<identifier> for <identifier> in <expr> do``
The `n for-in-do` expression must match ``<identifier> for <identifier> in <expr> do``.
A ``if <expr> then`` expression might be required.
Example:
```lua
@ -28,14 +29,14 @@ end
-- list comprehensions
local t = {1,2,3,4,5,6,7,8,9}
local onlyEven = {for n in t do if n%2 == 0 then n}
local onlyEven = {n for n in t do if n%2 == 0}
```
## Drawbacks
List comprehensions may be misused.
The list comprehensions have similar drawbacks to the if expression drawbacks
The list comprehensions have similar drawbacks to the if expression drawbacks.
https://github.com/Roblox/luau/blob/master/rfcs/syntax-if-expression.md
## Alternatives
@ -62,7 +63,7 @@ let vector = c![x, for x in 1..10, if x % 2 == 0];
```
## Function syntax
List comprehensions could be implemented as functions with ``table.map`` or ``table.filter``
List comprehensions could be implemented as functions with ``table.map`` or ``table.filter`` .
### Examples: