| Maintainer | judah.jacobson@gmail.com |
|---|---|
| Stability | experimental |
| Portability | portable (FFI) |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
System.Console.Terminfo.Base
Description
This module provides a low-level interface to the C functions of the terminfo library.
NOTE: Since this library is built on top of the curses interface, it is not thread-safe.
Synopsis
- data Terminal
- setupTerm :: String -> IO Terminal
- setupTermFromEnv :: IO Terminal
- data SetupTermError
- data Capability a
- getCapability :: Terminal -> Capability a -> Maybe a
- tiGetFlag :: String -> Capability Bool
- tiGuardFlag :: String -> Capability ()
- tiGetNum :: String -> Capability Int
- tiGetStr :: String -> Capability String
- tiGetOutput1 :: forall f. OutputCap f => String -> Capability f
- class OutputCap f
- class (Monoid s, OutputCap s) => TermStr s
- data TermOutput
- runTermOutput :: Terminal -> TermOutput -> IO ()
- hRunTermOutput :: Handle -> Terminal -> TermOutput -> IO ()
- termText :: String -> TermOutput
- tiGetOutput :: String -> Capability ([Int] -> LinesAffected -> TermOutput)
- type LinesAffected = Int
- class Semigroup a => Monoid a where
- (<#>) :: Monoid m => m -> m -> m
Initialization
setupTerm :: String -> IO Terminal Source #
Initialize the terminfo library to the given terminal entry.
Throws a SetupTermError if the terminfo database could not be read.
setupTermFromEnv :: IO Terminal Source #
Initialize the terminfo library, using the TERM environmental variable.
If TERM is not set, we use the generic, minimal entry dumb.
Throws a SetupTermError if the terminfo database could not be read.
data SetupTermError Source #
Instances
| Show SetupTermError # | |
Defined in System.Console.Terminfo.Base | |
| Exception SetupTermError # | |
Defined in System.Console.Terminfo.Base Methods toException :: SetupTermError -> SomeException Source # fromException :: SomeException -> Maybe SetupTermError Source # | |
Capabilities
data Capability a Source #
A feature or operation which a Terminal may define.
Instances
getCapability :: Terminal -> Capability a -> Maybe a Source #
tiGetFlag :: String -> Capability Bool Source #
Look up a boolean capability in the terminfo database.
Unlike tiGuardFlag, this capability never fails; it returns False if the
capability is absent or set to false, and returns True otherwise.
tiGuardFlag :: String -> Capability () Source #
Look up a boolean capability in the terminfo database, and fail if it's not defined.
tiGetStr :: String -> Capability String Source #
Deprecated: use tiGetOutput instead.
Look up a string capability in the terminfo database. NOTE: This function is deprecated; use
tiGetOutput1 instead.
Output
Terminfo contains many string capabilities for special effects.
For example, the cuu1 capability moves the cursor up one line; on ANSI terminals
this is accomplished by printing the control sequence "\ESC[A".
However, some older terminals also require "padding", or short pauses, after certain commands.
For example, when TERM=vt100 the cuu1 capability is "\ESC[A$<2>", which instructs terminfo
to pause for two milliseconds after outputting the control sequence.
The TermOutput monoid abstracts away all padding and control
sequence output. Unfortunately, that datatype is difficult to integrate into existing String-based APIs
such as pretty-printers. Thus, as a workaround, tiGetOutput1 also lets us access the control sequences as Strings. The one caveat is that it will not allow you to access padded control sequences as Strings. For example:
> t <- setupTerm "vt100" > isJust (getCapability t (tiGetOutput1 "cuu1") :: Maybe String) False > isJust (getCapability t (tiGetOutput1 "cuu1") :: Maybe TermOutput) True
String capabilities will work with software-based terminal types such as xterm and linux.
However, you should use TermOutput if compatibility with older terminals is important.
Additionally, the visualBell capability which flashes the screen usually produces its effect with a padding directive, so it will only work with TermOutput.
tiGetOutput1 :: forall f. OutputCap f => String -> Capability f Source #
Look up an output capability which takes a fixed number of parameters
(for example, Int -> Int -> TermOutput).
For capabilities which may contain variable-length
padding, use tiGetOutput instead.
Minimal complete definition
hasOkPadding, outputCap
Instances
| OutputCap TermOutput # | |
Defined in System.Console.Terminfo.Base Methods hasOkPadding :: TermOutput -> String -> Bool outputCap :: ([Int] -> String) -> [Int] -> TermOutput | |
| OutputCap [Char] # | |
Defined in System.Console.Terminfo.Base | |
| (Enum p, OutputCap f) => OutputCap (p -> f) # | |
Defined in System.Console.Terminfo.Base | |
class (Monoid s, OutputCap s) => TermStr s Source #
Instances
| TermStr TermOutput # | |
Defined in System.Console.Terminfo.Base | |
| TermStr [Char] # | |
Defined in System.Console.Terminfo.Base | |
TermOutput
data TermOutput Source #
An action which sends output to the terminal. That output may mix plain text with control characters and escape sequences, along with delays (called "padding") required by some older terminals.
Instances
| Semigroup TermOutput # | |
Defined in System.Console.Terminfo.Base Methods (<>) :: TermOutput -> TermOutput -> TermOutput Source # sconcat :: NonEmpty TermOutput -> TermOutput Source # stimes :: Integral b => b -> TermOutput -> TermOutput Source # | |
| Monoid TermOutput # | |
Defined in System.Console.Terminfo.Base Methods mempty :: TermOutput Source # mappend :: TermOutput -> TermOutput -> TermOutput Source # mconcat :: [TermOutput] -> TermOutput Source # | |
| TermStr TermOutput # | |
Defined in System.Console.Terminfo.Base | |
| OutputCap TermOutput # | |
Defined in System.Console.Terminfo.Base Methods hasOkPadding :: TermOutput -> String -> Bool outputCap :: ([Int] -> String) -> [Int] -> TermOutput | |
runTermOutput :: Terminal -> TermOutput -> IO () Source #
Write the terminal output to the standard output device.
hRunTermOutput :: Handle -> Terminal -> TermOutput -> IO () Source #
Write the terminal output to the terminal or file managed by the given
Handle.
termText :: String -> TermOutput Source #
tiGetOutput :: String -> Capability ([Int] -> LinesAffected -> TermOutput) Source #
Look up an output capability in the terminfo database.
type LinesAffected = Int Source #
A parameter to specify the number of lines affected. Some capabilities
(e.g., clear and dch1) use
this parameter on some terminals to compute variable-length padding.
Monoid functions
class Semigroup a => Monoid a where Source #
The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:
- Right identity
x<>mempty= x- Left identity
mempty<>x = x- Associativity
x(<>(y<>z) = (x<>y)<>zSemigrouplaw)- Concatenation
mconcat=foldr(<>)mempty
The method names refer to the monoid of lists under concatenation, but there are many other instances.
Some types can be viewed as a monoid in more than one way,
e.g. both addition and multiplication on numbers.
In such cases we often define newtypes and make those instances
of Monoid, e.g. Sum and Product.
NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.
Minimal complete definition
Methods
Identity of mappend
>>>"Hello world" <> mempty"Hello world"
mappend :: a -> a -> a Source #
An associative operation
NOTE: This method is redundant and has the default
implementation mappend = (<>)mappend is a synonym for
(<>), it is expected that the two functions are defined the same
way. In a future GHC release mappend will be removed from Monoid.
Fold a list using the monoid.
For most types, the default definition for mconcat will be
used, but the function is included in the class definition so
that an optimized version can be provided for specific types.
>>>mconcat ["Hello", " ", "Haskell", "!"]"Hello Haskell!"
Instances
| Monoid Ordering | Since: base-2.1 |
| Monoid () | Since: base-2.1 |
| Monoid TermOutput # | |
Defined in System.Console.Terminfo.Base Methods mempty :: TermOutput Source # mappend :: TermOutput -> TermOutput -> TermOutput Source # mconcat :: [TermOutput] -> TermOutput Source # | |
| Monoid [a] | Since: base-2.1 |
| Semigroup a => Monoid (Maybe a) | Lift a semigroup into Since 4.11.0: constraint on inner Since: base-2.1 |
| Monoid a => Monoid (IO a) | Since: base-4.9.0.0 |
| Monoid a => Monoid (a) | Since: base-4.15 |
| (Ord a, Bounded a) => Monoid (Min a) | Since: base-4.9.0.0 |
| (Ord a, Bounded a) => Monoid (Max a) | Since: base-4.9.0.0 |
| Monoid m => Monoid (WrappedMonoid m) | Since: base-4.9.0.0 |
Defined in Data.Semigroup Methods mempty :: WrappedMonoid m Source # mappend :: WrappedMonoid m -> WrappedMonoid m -> WrappedMonoid m Source # mconcat :: [WrappedMonoid m] -> WrappedMonoid m Source # | |
| Semigroup a => Monoid (Option a) | Since: base-4.9.0.0 |
| Monoid b => Monoid (a -> b) | Since: base-2.1 |
| (Monoid a, Monoid b) => Monoid (a, b) | Since: base-2.1 |
| Monoid (Proxy s) | Since: base-4.7.0.0 |
| (Monoid a, Monoid b, Monoid c) => Monoid (a, b, c) | Since: base-2.1 |
| Monoid a => Monoid (Const a b) | Since: base-4.9.0.0 |
| (Monoid a, Monoid b, Monoid c, Monoid d) => Monoid (a, b, c, d) | Since: base-2.1 |
| (Monoid a, Monoid b, Monoid c, Monoid d, Monoid e) => Monoid (a, b, c, d, e) | Since: base-2.1 |