stop using "pass by reference"-term in noteworthy difference

doc/src/manual/noteworthy-differences.md

@@ -7,9 +7,9 @@ major syntactic and functional differences. The following are some noteworthy di
 may trip up Julia users accustomed to MATLAB:
 
   * Julia arrays are indexed with square brackets, `A[i,j]`.
-  * Julia arrays are assigned by reference. After `A=B`, changing elements of `B` will modify `A`
+  * Julia arrays are not copied when assigned to another variable. After `A = B`, changing elements of `B` will modify `A`
     as well.
-  * Julia values are passed and assigned by reference. If a function modifies an array, the changes
+  * Julia values are not copied when passed to a function. If a function modifies an array, the changes
     will be visible in the caller.
   * Julia does not automatically grow arrays in an assignment statement. Whereas in MATLAB `a(4) = 3.2`
     can create the array `a = [0 0 0 3.2]` and `a(5) = 7` can grow it into `a = [0 0 0 3.2 7]`, the
@@ -153,7 +153,7 @@ For users coming to Julia from R, these are some noteworthy differences:
   * Julia encourages users to write their own types, which are easier to use than S3 or S4 objects
     in R. Julia's multiple dispatch system means that `table(x::TypeA)` and `table(x::TypeB)` act
     like R's `table.TypeA(x)` and `table.TypeB(x)`.
-  * In Julia, values are passed and assigned by reference. If a function modifies an array, the changes
+  * In Julia, values are not copied when assigned or passed to a function. If a function modifies an array, the changes
     will be visible in the caller. This is very different from R and allows new functions to operate
     on large data structures much more efficiently.
   * In Julia, vectors and matrices are concatenated using [`hcat`](@ref), [`vcat`](@ref) and
@@ -227,13 +227,13 @@ For users coming to Julia from R, these are some noteworthy differences:
     This syntax is not just syntactic sugar for a reference to a pointer or address as in C/C++. See
     the Julia documentation for the syntax for array construction (it has changed between versions).
   * In Julia, indexing of arrays, strings, etc. is 1-based not 0-based.
-  * Julia arrays are assigned by reference. After `A=B`, changing elements of `B` will modify `A`
+  * Julia arrays are not copied when assigned to another variable. After `A = B`, changing elements of `B` will modify `A`
     as well. Updating operators like `+=` do not operate in-place, they are equivalent to `A = A + B`
     which rebinds the left-hand side to the result of the right-hand side expression.
   * Julia arrays are column major (Fortran ordered) whereas C/C++ arrays are row major ordered by
     default. To get optimal performance when looping over arrays, the order of the loops should be
     reversed in Julia relative to C/C++ (see relevant section of [Performance Tips](@ref man-performance-tips)).
-  * Julia values are passed and assigned by reference. If a function modifies an array, the changes
+  * Julia values are not copied when assigned or passed to a function. If a function modifies an array, the changes
     will be visible in the caller.
   * In Julia, whitespace is significant, unlike C/C++, so care must be taken when adding/removing
     whitespace from a Julia program.