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diff --git a/docs/users_guide/parallel.xml b/docs/users_guide/parallel.xml
index 7792ea6..96e4e56 100644
--- a/docs/users_guide/parallel.xml
+++ b/docs/users_guide/parallel.xml
@@ -5,7 +5,7 @@
GHC implements some major extensions to Haskell to support
- concurrent and parallel programming. Let us first etablish terminology:
+ concurrent and parallel programming. Let us first establish terminology:
Parallelism means running
a Haskell program on multiple processors, with the goal of improving
@@ -33,7 +33,7 @@
url="http://research.microsoft.com/copyright/accept.asp?path=/users/simonpj/papers/concurrent-haskell.ps.gz">
Concurrent Haskell paper is still an excellent
resource, as is Tackling
+ url="http://research.microsoft.com/%7Esimonpj/papers/marktoberdorf/">Tackling
the awkward squad.
To the programmer, Concurrent Haskell introduces no new language constructs;
@@ -83,7 +83,7 @@ All these features are described in the papers mentioned earlier.
By default GHC runs your program on one processor; if you
want it to run in parallel you must link your program
with the , and run it with the RTS
- option; see ).
+ option; see ).
The runtime will
schedule the running Haskell threads among the available OS
threads, running as many in parallel as you specified with the
@@ -110,7 +110,7 @@ All these features are described in the papers mentioned earlier.
linkend="concurrent-haskell"/>), but the simplest mechanism for extracting parallelism from pure code is
to use the par combinator, which is closely related to (and often used
with) seq. Both of these are available from Control.Parallel:
+ url="../libraries/parallel/Control-Parallel.html">Control.Parallel:
infixr 0 `par`
@@ -136,7 +136,7 @@ import Control.Parallel
nfib :: Int -> Int
nfib n | n <= 1 = 1
- | otherwise = par n1 (seq n2 (n1 + n2))
+ | otherwise = par n1 (seq n2 (n1 + n2 + 1))
where n1 = nfib (n-1)
n2 = nfib (n-2)
@@ -149,8 +149,8 @@ nfib n | n <= 1 = 1
(leaving the parent to evaluate the other branch). Also, we must use
seq to ensure that the parent will evaluate
n2beforen1
- in the expression (n1 + n2). It is not sufficient
- to reorder the expression as (n2 + n1), because
+ in the expression (n1 + n2 + 1). It is not sufficient
+ to reorder the expression as (n2 + n1 + 1), because
the compiler may not generate code to evaluate the addends from left to
right.
@@ -163,7 +163,7 @@ nfib n | n <= 1 = 1
More sophisticated combinators for expressing parallelism are
available from the Control.Parallel.Strategies module.
+ url="../libraries/parallel/Control-Parallel-Strategies.html">Control.Parallel.Strategies module.
This module builds functionality around par,
expressing more elaborate patterns of parallel computation, such as
parallel map.