[fortran/en] do concurrent (#4531)

1 files changed, 29 insertions, 0 deletions

diff --git a/fortran.html.markdown b/fortran.html.markdown
index c0d90367..83074073 100644
--- a/fortran.html.markdown
+++ b/fortran.html.markdown
@@ -438,6 +438,35 @@ contains
     end function complex_abs
 
 end module fruity
+
+! ISO Standard Fortran 2008 introduced the DO CONCURRENT construct to allow you
+! to express loop-level parallelism
+
+integer :: i
+real :: array(100)
+
+DO CONCURRENT (i = 1:size(array))
+    array(i) = sqrt(i**i)
+END DO
+
+
+! Only calls to pure functions are allowed inside the loop and we can declare
+! multiple indices:
+
+integer :: x, y
+real :: array(8, 16)
+
+do concurrent (x = 1:size(array, 1), y = 1:size(array, 2))
+    array(x, y) = real(x)
+end do
+
+! loop indices can also declared inside the contruct:
+
+real :: array(8, 16)
+
+do concurrent (integer :: x = 1:size(array, 1), y = 1:size(array, 2))
+    array(x, y) = real(x)
+end do
 ```
 
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