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diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index 7d07f9b..b1e36ec 100644
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -1017,7 +1017,7 @@ right :: [a]
The execution continued at the point it previously stopped, and has
now stopped at the breakpoint for a second time.
-
+
Setting breakpoints
Breakpoints can be set in various ways. Perhaps the easiest way to
@@ -1106,10 +1106,14 @@ right :: [a]
Single-stepping is a great way to visualise the execution of your
program, and it is also a useful tool for identifying the source of a
- bug. The concept is simple: single-stepping enables all the
- breakpoints in the program and executes until the next breakpoint is
- reached, at which point you can single-step again, or continue
- normally. For example:
+ bug. GHCi offers two variants of stepping. Use
+ :step to enable all the
+ breakpoints in the program, and execute until the next breakpoint is
+ reached. Use :steplocal to limit the set
+ of enabled breakpoints to those in the current top level function.
+ Similarly, use :stepmodule to single step only on
+ breakpoints contained in the current module.
+ For example:
*Main> :step main
@@ -1118,10 +1122,11 @@ _result :: IO ()
The command :step
- expr begins the evaluation of
+ expr begins the evaluation of
expr in single-stepping mode. If
expr is ommitted, then it single-steps from
- the current breakpoint.
+ the current breakpoint. :stepover
+ works similarly.
The :list command is particularly useful when
single-stepping, to see where you currently are:
@@ -1330,9 +1335,13 @@ a :: a
:trace and :history to establish
the context. However, head is in a library and
we can't set a breakpoint on it directly. For this reason, GHCi
- provides the flag -fbreak-on-exception which causes
- the evaluator to stop when an exception is thrown, just as it does when
- a breakpoint is hit. This is only really useful in conjunction with
+ provides the flags -fbreak-on-exception which causes
+ the evaluator to stop when an exception is thrown, and
+ -fbreak-on-error, which works similarly but stops only on
+ uncaught exceptions. When stopping at an exception, GHCi will act
+ just as it does when a breakpoint is hit, with the deviation that it
+ will not show you any source code location. Due to this, these
+ commands are only really useful in conjunction with
:trace, in order to log the steps leading up to the
exception. For example:
@@ -1704,16 +1713,6 @@ $ ghci -lm
- :continue
- :continue
-
- Continue the current evaluation, when stopped at a
- breakpoint.
-
-
-
-
-
:cmd expr
:cmd
@@ -1728,6 +1727,16 @@ $ ghci -lm
+ :continue
+ :continue
+
+ Continue the current evaluation, when stopped at a
+ breakpoint.
+
+
+
+
+
:ctags filename
:etags filename
:etags
@@ -1737,7 +1746,8 @@ $ ghci -lm
Generates a “tags” file for Vi-style editors
- (:ctags) or Emacs-style editors (etags). If
+ (:ctags) or
+ Emacs-style editors (:etags). If
no filename is specified, the defaulit tags or
TAGS is
used, respectively. Tags for all the functions, constructors and
@@ -1845,6 +1855,15 @@ Prelude> :. cmds.ghci
+ :etags
+
+
+ See :ctags.
+
+
+
+
+
:force identifier ...
:force
@@ -1913,6 +1932,12 @@ Prelude> :. cmds.ghci
will be printed. If name has
been loaded from a source file, then GHCi will also display
the location of its definition in the source.
+ For types and classes, GHCi also summarises instances that
+ mention them. To avoid showing irrelevant information, an instance
+ is shown only if (a) its head mentions name,
+ and (b) all the other things mentioned in the instance
+ are in scope (either qualified or otherwise) as a result of
+ a :load or :module commands.
@@ -1981,7 +2006,7 @@ Prelude> :. cmds.ghci
However, we cannot simply pass the arguments to the
main function while we are testing in ghci,
as the main function doesn't take its
- directly.
+ arguments directly.
@@ -2026,7 +2051,7 @@ Prelude> :main foo bar
Prints a value without forcing its evaluation.
:print may be used on values whose types are
- unkonwn or partially known, which might be the case for local
+ unknown or partially known, which might be the case for local
variables with polymorphic types at a breakpoint. While inspecting
the runtime value, :print attempts to
reconstruct the type of the value, and will elaborate the type in
@@ -2046,7 +2071,7 @@ Prelude> :main foo bar
:quit
- Quits GHCi. You can also quit by typing a control-D
+ Quits GHCi. You can also quit by typing control-D
at the prompt.
@@ -2191,7 +2216,7 @@ Prelude> :main foo bar
:show modules
- Show the list of modules currently load.
+ Show the list of modules currently loaded.
@@ -2302,7 +2327,7 @@ Prelude> :main foo bar
The :set command sets two types of
options: GHCi options, which begin with
- ‘+” and “command-line”
+ ‘+’, and “command-line”
options, which begin with ‘-’.
NOTE: at the moment, the :set command
@@ -2414,9 +2439,10 @@ Prelude> :set -fno-glasgow-exts
startupfiles, GHCi
- When it starts, GHCi always reads and executes commands from
- $HOME/.ghci, followed by
- ./.ghci.
+ When it starts, unless the -ignore-dot-ghci
+ flag is given, GHCi reads and executes commands from
+ ./.ghci, followed by
+ $HOME/.ghci.
The .ghci in your home directory is
most useful for turning on favourite options (eg. :set
@@ -2425,7 +2451,7 @@ Prelude> :set -fno-glasgow-exts
project is a useful way to set certain project-wide options so you
don't have to type them everytime you start GHCi: eg. if your
project uses GHC extensions and CPP, and has source files in three
- subdirectories A B and C, you might put the following lines in
+ subdirectories A, B and C, you might put the following lines in
.ghci:
@@ -2573,7 +2599,19 @@ Prelude> :set -fno-glasgow-exts
I can't use Control-C to interrupt computations in
GHCi on Windows.
- See
+ See .
+
+
+
+
+ The default buffering mode is different in GHCi to GHC.
+
+
+ In GHC, the stdout handle is line-buffered by default.
+ However, in GHCi we turn off the buffering on stdout,
+ because this is normally what you want in an interpreter:
+ output appears as it is generated.
+