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| author | Richard Eisenberg <eir@cis.upenn.edu> | 2014-12-08 10:59:48 -0500 |
|---|---|---|
| committer | Richard Eisenberg <eir@cis.upenn.edu> | 2014-12-08 10:59:48 -0500 |
| commit | b06908b5a120ed56df5416019c38576aadcd21e2 (patch) | |
| tree | 0d8adcdbccb94fa66693f343df429c31444f5e5a /docs | |
| parent | 5818378db95a97cb4760afdab41bdf8f6ed07272 (diff) | |
| download | haskell-b06908b5a120ed56df5416019c38576aadcd21e2.tar.gz | |
Fix #9871 by clarifying documentation.
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/users_guide/glasgow_exts.xml | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml index 18809fdcf3..2c6cb6a6d3 100644 --- a/docs/users_guide/glasgow_exts.xml +++ b/docs/users_guide/glasgow_exts.xml @@ -9174,21 +9174,29 @@ f n = \ [haskell|y|] -> y+n </para> </listitem> <listitem> - <para> - The type environment seen by <literal>reify</literal> includes - all the top-level declaration up to the end of the immediately - preceding <emphasis>declaration group</emphasis>, but no more. + <para> + Top-level declaration splices break up a source file into + <emphasis>delcaration groups</emphasis>. A + <emphasis>declaration group</emphasis> is the group of + declarations created by a top-level declaration splice, plus + those following it, down to but not including the next + top-level declaration splice. The first declaration group in a + module includes all top-level definitions down to but not + including the first top-level declaration splice. </para> <para> - A <emphasis>declaration group</emphasis> is the group of - declarations created by a top-level declaration splice, plus - those following it, down to but not including the next top-level - declaration splice. The first declaration group in a module - includes all top-level definitions down to but not including the - first top-level declaration splice. + Each declaration group is mutually recursive only within + the group. Declaration groups can refer to definitions within + previous groups, but not later ones. </para> + <para> + Accordingly, the type environment seen by + <literal>reify</literal> includes all the top-level + declarations up to the end of the immediately preceding + declaration group, but no more. + </para> <para> Concretely, consider the following code @@ -9206,6 +9214,11 @@ module M where <orderedlist> <listitem> <para> + The body of <literal>h</literal> would be unable to refer + to the function <literal>w</literal>. + </para> + + <para> A <literal>reify</literal> inside the splice <literal>$(th1 ..)</literal> would see the definition of <literal>f</literal>. |