About Variables / Default Variables

http://lesscss.cn/features/#variables-feature-default-variables
It writes:
We sometimes get requests for default variables - an ability to set a variable only if it is not already set.

This feature is not required because you can easily override a variable by putting the definition afterwards.

For instance:

// library
@base-color: green;
@dark-color: darken(@base-color, 10%);

// use of library
@import "library.less";
@base-color: red;

This works fine because of Lazy Loading - base-color is overridden and dark-color is a dark red.

I don't think the behavior in the example meets the instruction, because the @base-color is already set to green, it shouldn't be reset to red.

So I think the instruction should be:
" We sometimes get requests for default variables - an ability to set a variable only if it is not already set.

This feature is conflicted with 'overriding a variable by putting the definition afterwards', so we couldn't implement the behavior of default variables."

Open the variables-feature-default-variables section at lesscss.cn/features/ and compare its explanation with the example in this issue. Update the documentation to state that default variables conflict with overriding a variable later, then verify that the revised wording accurately describes the example.