X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fghci.xml;h=69078d5093ebb2e0489bf0d06d74a7f16594cdc1;hb=6fa4feaf2979419a6f6153ffa80c22a28f2f654f;hp=45ac5a643bae7bd7557d8619fc05277281ac5e47;hpb=742722477ac2edcb142747aa9ab99345eeb454ed;p=ghc-hetmet.git
diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index 45ac5a6..69078d5 100644
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -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:
@@ -1923,6 +1928,12 @@ 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.
@@ -2312,7 +2323,7 @@ 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
@@ -2424,9 +2435,10 @@ 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
@@ -2435,7 +2447,7 @@ 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:
@@ -2583,7 +2595,19 @@ 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.
+