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| author | RyanGlScott <ryan.gl.scott@ku.edu> | 2015-07-17 00:05:14 +0200 |
|---|---|---|
| committer | Ben Gamari <ben@smart-cactus.org> | 2015-07-17 00:08:10 +0200 |
| commit | 2c9de9c9a3df8e855c883139b0cb2fd41801bd67 (patch) | |
| tree | 537691587672cacd63f077ec38d36094e7e5fb59 /docs | |
| parent | 2c5c29722c78e089eda0baa7ff89154b58f23165 (diff) | |
| download | haskell-2c9de9c9a3df8e855c883139b0cb2fd41801bd67.tar.gz | |
Handle Char#, Addr# in TH quasiquoter (fixes #10620)
DsMeta does not attempt to handle quasiquoted Char# or Addr# values,
which causes expressions like `$([| 'a'# |])` or `$([| "abc"# |])` to
fail
with an `Exotic literal not (yet) handled by Template Haskell` error.
To fix this, the API of `template-haskell` had to be changed so that
`Lit`
now has an extra constructor `CharPrimL` (a `StringPrimL` constructor
already
existed, but it wasn't used). In addition, `DsMeta` has to manipulate
`CoreExpr`s directly that involve `Word8`s. In order to do this,
`Word8` had
to be added as a wired-in type to `TysWiredIn`.
Actually converting from `HsCharPrim` and `HsStringPrim` to `CharPrimL`
and
`StringPrimL`, respectively, is pretty straightforward after that, since
both `HsCharPrim` and `CharPrimL` use `Char` internally, and
`HsStringPrim`
uses a `ByteString` internally, which can easily be converted to
`[Word8]`,
which is what `StringPrimL` uses.
Reviewers: goldfire, austin, simonpj, bgamari
Reviewed By: simonpj, bgamari
Subscribers: thomie
Differential Revision: https://phabricator.haskell.org/D1054
GHC Trac Issues: #10620
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/users_guide/glasgow_exts.xml | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml index 22934fa94c..a9a85fa5ea 100644 --- a/docs/users_guide/glasgow_exts.xml +++ b/docs/users_guide/glasgow_exts.xml @@ -9822,7 +9822,43 @@ module M where </orderedlist> </para> </listitem> - + <listitem> + <para> + Expression quotations accept most Haskell language constructs. + However, there are some GHC-specific extensions which expression + quotations currently do not support, including + <itemizedlist> + <listitem> + <para> + Recursive <literal>do</literal>-statements (see + <ulink url="https://ghc.haskell.org/trac/ghc/ticket/1262"> + Trac #1262</ulink>) + </para> + </listitem> + <listitem> + <para> + Pattern synonyms (see + <ulink url="https://ghc.haskell.org/trac/ghc/ticket/8761"> + Trac #8761</ulink>) + </para> + </listitem> + <listitem> + <para> + Typed holes (see + <ulink url="https://ghc.haskell.org/trac/ghc/ticket/10267"> + Trac #10267</ulink>) + </para> + </listitem> + <listitem> + <para> + Partial type signatures (see + <ulink url="https://ghc.haskell.org/trac/ghc/ticket/10548"> + Trac #10548</ulink>) + </para> + </listitem> + </itemizedlist> + </para> + </listitem> </itemizedlist> (Compared to the original paper, there are many differences of detail. |