Let

The .let function defines a temporary variable, accessible only within its scope. It accepts two parameters:

1. The value, of any type, to assign to the scoped variable;
2. A lambda block that accepts one parameter (the given value, indeed)

.let {.multiply {4} {2}}
  area:
  The area of the rectangle is .area.
  If it were a triangle, it would have been .divide {.area} by:{2}.

The area of the rectangle is 8.
If it were a triangle, it would have been 4.

 

The function returns the evaluation of the lambda, thus it can be used as an expression:

.center
  .let {Quarkdown}
    name:
    .uppercase {.name}, .lowercase {.name}, .capitalize {.name}

 

The lambda block accepts implicit positional parameters (see lambda)

.center
  .let {Quarkdown}
    .uppercase {.1}, .lowercase {.1}, .capitalize {.1}