Maintainer | [email protected] |
---|---|
Stability | experimental |
Portability | portable (FFI) |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
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.
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
Show SetupTermError | |
Defined in System.Console.Terminfo.Base MethodsshowsPrec :: Int -> SetupTermError -> ShowS Source show :: SetupTermError -> String Source showList :: [SetupTermError] -> ShowS Source | |
Exception SetupTermError | |
Defined in System.Console.Terminfo.Base MethodstoException :: SetupTermError -> SomeException Source fromException :: SomeException -> Maybe SetupTermError Source |
data Capability a Source
A feature or operation which a Terminal
may define.
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.
tiGetNum :: String -> Capability Int Source
Look up a numeric capability in the terminfo database.
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.
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 String
s. 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.
hasOkPadding, outputCap
OutputCap TermOutput | |
Defined in System.Console.Terminfo.Base MethodshasOkPadding :: 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
TermStr TermOutput | |
Defined in System.Console.Terminfo.Base | |
TermStr [Char] | |
Defined in System.Console.Terminfo.Base |
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.
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 Methodsmappend :: TermOutput -> TermOutput -> TermOutput Source mconcat :: [TermOutput] -> TermOutput Source | |
TermStr TermOutput | |
Defined in System.Console.Terminfo.Base | |
OutputCap TermOutput | |
Defined in System.Console.Terminfo.Base MethodshasOkPadding :: 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.
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:
x <> mempty = x
mempty <> x = x
x <> (y <> z) = (x <> y) <> z
(Semigroup
law)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 newtype
s and make those instances of Monoid
, e.g. Sum
and Product
.
NOTE: Semigroup
is a superclass of Monoid
since base-4.11.0.0.
Identity of mappend
An associative operation
NOTE: This method is redundant and has the default implementation mappend = (<>)
since base-4.11.0.0.
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.
Monoid Ordering | Since: base-2.1 |
Monoid () | Since: base-2.1 |
Monoid TermOutput | |
Defined in System.Console.Terminfo.Base Methodsmappend :: 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 |
(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 Methodsmempty :: 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 |
(<#>) :: Monoid m => m -> m -> m infixl 2 Source
An operator version of mappend
.
© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/8.8.3/docs/html/libraries/terminfo-0.4.1.4/System-Console-Terminfo-Base.html