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file

Implements the file based methods.

These are Mojo built-ins, so you don't need to import them.

For example, here's how to read a file:

var  f = open("my_file.txt", "r")
print(f.read())
f.close()

Or use a with statement to close the file automatically:

with open("my_file.txt", "r") as f:
print(f.read())

FileHandle

File handle to an opened file.

Fields:

  • handle (DTypePointer[invalid, 0]): The underlying pointer to the file handle.

Implemented traits:

AnyType

Methods:

__init__

__init__(inout self: Self)

Default constructor.

__init__(inout self: Self, path: String, mode: String)

Construct the FileHandle using the file path and mode.

Args:

  • path (String): The file path.
  • mode (String): The mode to open the file in (the mode can be "r" or "w").

__init__(inout self: Self, path: StringRef, mode: StringRef)

Construct the FileHandle using the file path and string.

Args:

  • path (StringRef): The file path.
  • mode (StringRef): The mode to open the file in (the mode can be "r" or "w").

__moveinit__

__moveinit__(inout self: Self, owned existing: Self)

Moves constructor for the file handle.

Args:

  • existing (Self): The existing file handle.

__del__

__del__(owned self: Self)

Closes the file handle.

close

close(inout self: Self)

Closes the file handle.

read

read(self: Self, size: SIMD[si64, 1]) -> String

Reads the data from the file.

Args:

  • size (SIMD[si64, 1]): Requested number of bytes to read.

Returns:

The contents of the file.

read_bytes

read_bytes(self: Self, size: SIMD[si64, 1]) -> List[SIMD[si8, 1]]

Read from file buffer until we have size characters or we hit EOF. If size is negative or omitted, read until EOF.

Args:

  • size (SIMD[si64, 1]): Requested number of bytes to read.

Returns:

The contents of the file.

seek

seek(self: Self, offset: SIMD[ui64, 1]) -> SIMD[ui64, 1]

Seeks to the given offset in the file.

Raises: An error if this file handle is invalid, or if file seek returned a failure.

Args:

  • offset (SIMD[ui64, 1]): The byte offset to seek to from the start of the file.

Returns:

The resulting byte offset from the start of the file.

write

write(self: Self, data: StringLiteral)

Write the data to the file.

Args:

  • data (StringLiteral): The data to write to the file.

write(self: Self, data: String)

Write the data to the file.

Args:

  • data (String): The data to write to the file.

write(self: Self, data: StringRef)

Write the data to the file.

Args:

  • data (StringRef): The data to write to the file.

__enter__

__enter__(owned self: Self) -> Self

The function to call when entering the context.

open

open(path: String, mode: String) -> FileHandle

Opens the file specified by path using the mode provided, returning a FileHandle.

Args:

  • path (String): The path to the file to open.
  • mode (String): The mode to open the file in.

Returns:

A file handle.

open[pathlike: PathLike](path: pathlike, mode: String) -> FileHandle

Opens the file specified by path using the mode provided, returning a FileHandle.

Parameters:

  • pathlike (PathLike): The a type conforming to the os.PathLike trait.

Args:

  • path (pathlike): The path to the file to open.
  • mode (String): The mode to open the file in (the mode can be "r" or "w").

Returns:

A file handle.