README
¶
file
file provides functions to interact with the file system. The library is inspired by file helpers from Amoy.
Functions
trim_bom(rd) string
Removes the Byte Order Mark (BOM) from a byte literal string or bytes.
Parameters
| name | type | description |
|---|---|---|
rd |
`string | byes` |
Examples
String
Removes the Byte Order Mark (BOM) from a string.
load("file", "trim_bom")
s = b'\xef\xbb\xbfhello'
print(trim_bom(s))
# Output: hello
count_lines(name) int
Counts the total lines in a file located at the provided path.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file whose lines are to be counted |
Examples
String
Count the lines of a file.
load("file", "count_lines")
name = 'path/to/file.txt'
print(count_lines(name))
# Output: 10
head_lines(name, n) []string
Returns the first 'n' lines of a file.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file |
n |
int |
The number of lines from the top to be returned |
Examples
String
Get the top 10 lines of a file.
load('file', 'head_lines')
print(head_lines('path/to/file.txt', 10))
# Output: ['line1', 'line2', ... 'line10']
tail_lines(name, n) []string
Returns the last 'n' lines of a file.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file |
n |
int |
The number of lines from the bottom to be returned |
Examples
String
Get the bottom 10 lines of a file.
load('file', 'tail_lines')
print(tail_lines('path/to/file.txt', 10))
# Output: ['line91', 'line92', ... 'line100']
read_bytes(name)
Reads a file and returns its contents as bytes.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be read |
Examples
String
Read a file in bytes.
load('file', 'read_bytes')
print(read_bytes('path/to/file.txt'))
# Output: b'file_content'
read_string(name)
Reads a file and returns its contents as string.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be read |
Examples
String
Read a file in string.
load('file', 'read_string')
print(read_string('path/to/file.txt'))
# Output: 'file_content'
read_lines(name)
Reads a file and returns its contents as a list of lines.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be read |
Examples
String
Get lines of a file in a list.
load('file', 'read_lines')
print(read_lines('path/to/file.txt'))
# Output: ['line1', 'line2', 'line3', ....]
write_bytes(name, data)
Writes/overwrites bytes or a byte literal string to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
string |
The byte literal string or bytes to be written to the file |
Examples
String
Write a byte string to a file.
load('file', 'write_bytes')
name = 'new_file.txt'
data = b'Hello, This is a new file.'
write_bytes(name, data)
write_string(name, data)
Writes/overwrites a string to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
string |
The string to be written to the file |
Examples
String
Write a string to a file.
load('file', 'write_string')
write_string('new_file.txt', 'Hello, This is a new file.')
write_lines(name, data)
Writes/overwrites a list, tuple or set of lines to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
`list | set |
Examples
List
Write a list of lines to a file.
load('file', 'write_lines')
lines = ['This is line1', 'This is line2', 'This is line3']
write_lines('new_file.txt', lines)
append_bytes(name, data)
Appends bytes or a byte literal string to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
string |
The byte literal string or bytes to be appended to the file |
Examples
String
Append a byte string to a file.
load('file', 'append_bytes')
append_bytes('existing_file.txt', b'Hello, This is appended data.')
append_string(name, data)
Appends a string to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
string |
The string to be appended to the file |
Examples
String
Append a string to a file.
load('file', 'append_string')
append_string('existing_file.txt', 'Hello, This is appended data.')
append_lines(name, data)
Appends a list, tuple or set of lines to a file. If the file isn't present, a new file would be created.
Parameters
| name | type | description |
|---|---|---|
name |
string |
The path of the file to be written to |
data |
`list | set |
Examples
List
Append a list of lines to a file.
load('file', 'append_lines')
append_lines('existing_file.txt', ['This is line1', 'This is line2', 'This is line3'])
Documentation
¶
Overview ¶
Package file defines functions that manipulate files, it's inspired by file helpers from Amoy.
Index ¶
- Constants
- Variables
- func AppendFileBytes(path string, data []byte) error
- func AppendFileLines(path string, lines []string) error
- func AppendFileString(path string, content string) error
- func CountFileLines(path string) (count int, err error)
- func LoadModule() (starlark.StringDict, error)
- func ReadFileBytes(path string) ([]byte, error)
- func ReadFileLines(path string) (lines []string, err error)
- func ReadFileString(path string) (string, error)
- func ReadFirstLines(path string, n int) (lines []string, err error)
- func ReadLastLines(path string, n int) (lines []string, err error)
- func TrimUTF8BOM(b []byte) []byte
- func WriteFileBytes(path string, data []byte) error
- func WriteFileLines(path string, lines []string) error
- func WriteFileString(path string, content string) error
- type LineFunc
Constants ¶
const ModuleName = "file"
ModuleName defines the expected name for this Module when used in starlark's load() function, eg: load('file', 'trim_bom')
Variables ¶
var ( // QuitRead indicates the arbitrary error means to quit from reading. QuitRead = errors.New("file: quit read by line") )
Functions ¶
func AppendFileBytes ¶
AppendFileBytes writes the given data to the end of a file.
func AppendFileLines ¶
AppendFileLines appends the given lines to the end of a text file.
func AppendFileString ¶
AppendFileString appends the given content string to the end of a file.
func CountFileLines ¶
CountFileLines counts all lines from the given file (the line ending chars are not included).
func LoadModule ¶
func LoadModule() (starlark.StringDict, error)
LoadModule loads the file module. It is concurrency-safe and idempotent.
func ReadFileBytes ¶
ReadFileBytes reads the whole named file and returns the contents. It's a sugar actually, simply calls os.ReadFile like ioutil.ReadFile does since Go 1.16.
func ReadFileLines ¶
ReadFileLines reads all lines from the given file (the line ending chars are not included).
func ReadFileString ¶
ReadFileString reads the whole named file and returns the contents as a string.
func ReadFirstLines ¶
ReadFirstLines reads the top n lines from the given file (the line ending chars are not included), or lesser lines if the given file doesn't contain enough line ending chars.
func ReadLastLines ¶
ReadLastLines reads the bottom n lines from the given file (the line ending chars are not included), or lesser lines if the given file doesn't contain enough line ending chars.
func TrimUTF8BOM ¶
TrimUTF8BOM removes the leading UTF-8 byte order mark from bytes.
func WriteFileBytes ¶
WriteFileBytes writes the given data into a file.
func WriteFileLines ¶
WriteFileLines writes the given lines as a text file.
func WriteFileString ¶
WriteFileString writes the given content string into a file.
Source Files