Effect type agnostic Console
with common methods to write to and read from the standard
console. Suited only for extremely simple console input and output.
- Example:
import cats.effect.std.Console import cats.effect.kernel.Sync import cats.syntax.all._ implicit val console = Console.sync[F] def myProgram[F[_]: Console]: F[Unit] = for { _ <- Console[F].println("Please enter your name: ") n <- Console[F].readLine _ <- if (n.nonEmpty) Console[F].println("Hello, " + n) else Console[F].errorln("Name is empty!") } yield ()
- Companion:
- object
Value members
Abstract methods
Prints a value to the standard error output using the implicit cats.Show
instance.
Prints a value to the standard error output using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard error output
Prints a value to the standard error output using the implicit cats.Show
instance.
Prints a value to the standard error output using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard error output
Prints a value to the standard error output followed by a new line using the implicit
cast.Show
instance.
Prints a value to the standard error output followed by a new line using the implicit
cast.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard error output
Prints a value to the standard error output followed by a new line using the implicit
cast.Show
instance.
Prints a value to the standard error output followed by a new line using the implicit
cast.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard error output
Prints a value to the standard output using the implicit cats.Show
instance.
Prints a value to the standard output using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard output
Prints a value to the standard output using the implicit cats.Show
instance.
Prints a value to the standard output using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard output
Prints a value to the standard output followed by a new line using the implicit cats.Show
instance.
Prints a value to the standard output followed by a new line using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard output
Prints a value to the standard output followed by a new line using the implicit cats.Show
instance.
Prints a value to the standard output followed by a new line using the implicit cats.Show
instance.
- Value parameters:
- S
implicit
cats.Show[A]
instance, defaults tocats.Show.fromToString
- a
value to be printed to the standard output
Reads a line as a string from the standard input using the provided charset.
Reads a line as a string from the standard input using the provided charset.
The effect can raise a java.io.EOFException
if no input has been consumed before the EOF
is observed. This should never happen with the standard input, unless it has been replaced
with a finite java.io.InputStream
through java.lang.System#setIn
or similar.
- Value parameters:
- charset
the
java.nio.charset.Charset
to be used when decoding the input stream
- Returns:
an effect that describes reading the user's input from the standard input as a string
Reads a line as a string from the standard input using the provided charset.
Reads a line as a string from the standard input using the provided charset.
The effect can raise a java.io.EOFException
if no input has been consumed before the EOF
is observed. This should never happen with the standard input, unless it has been replaced
with a finite java.io.InputStream
through java.lang.System#setIn
or similar.
- Value parameters:
- charset
the
java.nio.charset.Charset
to be used when decoding the input stream
- Returns:
an effect that describes reading the user's input from the standard input as a string
Concrete methods
Modifies the context in which this console operates using the natural transformation f
.
Modifies the context in which this console operates using the natural transformation f
.
- Returns:
a console in the new context obtained by mapping the current one using
f
Modifies the context in which this console operates using the natural transformation f
.
Modifies the context in which this console operates using the natural transformation f
.
- Returns:
a console in the new context obtained by mapping the current one using
f
Prints the stack trace of the given Throwable to standard error output.
Prints the stack trace of the given Throwable to standard error output.
Prints the stack trace of the given Throwable to standard error output.
Prints the stack trace of the given Throwable to standard error output.
Reads a line as a string from the standard input using the platform's default charset, as
per java.nio.charset.Charset.defaultCharset()
.
Reads a line as a string from the standard input using the platform's default charset, as
per java.nio.charset.Charset.defaultCharset()
.
The effect can raise a java.io.EOFException
if no input has been consumed before the EOF
is observed. This should never happen with the standard input, unless it has been replaced
with a finite java.io.InputStream
through java.lang.System#setIn
or similar.
- Returns:
an effect that describes reading the user's input from the standard input as a string
Reads a line as a string from the standard input using the platform's default charset, as
per java.nio.charset.Charset.defaultCharset()
.
Reads a line as a string from the standard input using the platform's default charset, as
per java.nio.charset.Charset.defaultCharset()
.
The effect can raise a java.io.EOFException
if no input has been consumed before the EOF
is observed. This should never happen with the standard input, unless it has been replaced
with a finite java.io.InputStream
through java.lang.System#setIn
or similar.
- Returns:
an effect that describes reading the user's input from the standard input as a string