[powershell/en] correct examples for arrays

Fixed incorrect examples for arrays.
Added information for tuple
Fixed wording for Hashtables
This commit is contained in:
Charliecoolblue 2022-10-04 17:15:08 +02:00 committed by GitHub
parent a52f5d2c26
commit b5ab0b7928
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

View File

@ -221,7 +221,7 @@ $defaultArray.Add("thing4") # => Exception "Collection was of a fixed size."
# ArrayLists store sequences # ArrayLists store sequences
[System.Collections.ArrayList]$array = @() [System.Collections.ArrayList]$array = @()
# You can start with a prefilled ArrayList # You can start with a prefilled ArrayList
[System.Collections.ArrayList]$otherArray = @(4, 5, 6) [System.Collections.ArrayList]$otherArray = @(5, 6, 7, 8)
# Add to the end of a list with 'Add' (Note: produces output, append to $null) # Add to the end of a list with 'Add' (Note: produces output, append to $null)
$array.Add(1) > $null # $array is now [1] $array.Add(1) > $null # $array is now [1]
@ -237,25 +237,14 @@ $array.Add(3) > $null # array is now [1, 2, 4, 3] again.
$array[0] # => 1 $array[0] # => 1
# Look at the last element # Look at the last element
$array[-1] # => 3 $array[-1] # => 3
# Looking out of bounds returns nothing # Looking out of bounds returns nothing
$array[4] # blank line returned $array[4] # blank line returned
# You can look at ranges with slice syntax. # Remove elements from a array
# The start index is included, the end index is not $array.Remove($array[3]) # $array is now [1, 2, 4]
# (It's a closed/open range for you mathy types.)
$array[1..3] # Return array from index 1 to 3 => [2, 4]
$array[2..-1] # Return array starting from index 2 => [4, 3]
$array[0..3] # Return array from beginning until index 3 => [1, 2, 4]
$array[0..2] # Return array selecting every second entry => [1, 4]
$array.Reverse() # mutates array to reverse order => [3, 4, 2, 1]
# Use any combination of these to make advanced slices
# Remove arbitrary elements from a array with "del" # Insert at index an element
$array.Remove($array[2]) # $array is now [1, 2, 3] $array.Insert(2, 3) # $array is now [1, 2, 3, 4]
# Insert an element at a specific index
$array.Insert(1, 2) # $array is now [1, 2, 3] again
# Get the index of the first item found matching the argument # Get the index of the first item found matching the argument
$array.IndexOf(2) # => 1 $array.IndexOf(2) # => 1
@ -263,16 +252,24 @@ $array.IndexOf(6) # Returns -1 as "outside array"
# You can add arrays # You can add arrays
# Note: values for $array and for $otherArray are not modified. # Note: values for $array and for $otherArray are not modified.
$array + $otherArray # => [1, 2, 3, 4, 5, 6] $array + $otherArray # => [1, 2, 3, 4, 5, 6, 7, 8]
# Concatenate arrays with "AddRange()" # Concatenate arrays with "AddRange()"
$array.AddRange($otherArray) # Now $array is [1, 2, 3, 4, 5, 6] $array.AddRange($otherArray) # Now $array is [1, 2, 3, 4, 5, 6, 7, 8]
# Check for existence in a array with "in" # Check for existence in a array with "in"
1 -in $array # => True 1 -in $array # => True
# Examine length with "Count" (Note: "Length" on arrayList = each items length) # Examine length with "Count" (Note: "Length" on arrayList = each items length)
$array.Count # => 6 $array.Count # => 8
# You can look at ranges with slice syntax.
$array[1,3,5] # Return selected index => [2, 4, 6]
$array[1..3] # Return from index 1 to 3 => [2, 3, 4]
$array[-3..-1] # Return from last 3 to last 1 => [6, 7, 8]
$array[-1..-3] # Return from last 1 to last 3 => [8, 7, 6]
$array[2..-1] # Return from index 2 to last (NOT as most expect) => [3, 2, 1, 8]
$array[0,2+4..6] # Return multiple ranges with the + => [1, 3, 5, 6, 7]
# Tuples are like arrays but are immutable. # Tuples are like arrays but are immutable.
@ -284,13 +281,14 @@ $tuple.Item(0) = 3 # Raises a TypeError
# You can do some of the array methods on tuples, but they are limited. # You can do some of the array methods on tuples, but they are limited.
$tuple.Length # => 3 $tuple.Length # => 3
$tuple + (4, 5, 6) # => Exception $tuple + (4, 5, 6) # => Exception
$tuple[0..2] # => $null $tuple[0..2] # => $null (in powershell 5) => [1, 2, 3] (in powershell 7)
2 -in $tuple # => False 2 -in $tuple # => False
# Hashtables store mappings from keys to values, similar to Dictionaries. # Hashtables store mappings from keys to values, similar to (but distinct from) Dictionaries.
# Hashtables do not hold entry order as arrays do.
$emptyHash = @{} $emptyHash = @{}
# Here is a prefilled dictionary # Here is a prefilled hashtable
$filledHash = @{"one"= 1 $filledHash = @{"one"= 1
"two"= 2 "two"= 2
"three"= 3} "three"= 3}
@ -299,7 +297,6 @@ $filledHash = @{"one"= 1
$filledHash["one"] # => 1 $filledHash["one"] # => 1
# Get all keys as an iterable with ".Keys". # Get all keys as an iterable with ".Keys".
# items maintain the order at which they are inserted into the dictionary.
$filledHash.Keys # => ["one", "two", "three"] $filledHash.Keys # => ["one", "two", "three"]
# Get all values as an iterable with ".Values". # Get all values as an iterable with ".Values".
@ -307,18 +304,18 @@ $filledHash.Values # => [1, 2, 3]
# Check for existence of keys or values in a hash with "-in" # Check for existence of keys or values in a hash with "-in"
"one" -in $filledHash.Keys # => True "one" -in $filledHash.Keys # => True
1 -in $filledHash.Values # => False 1 -in $filledHash.Values # => False (in powershell 5) => True (in powershell 7)
# Looking up a non-existing key returns $null # Looking up a non-existing key returns $null
$filledHash["four"] # $null $filledHash["four"] # $null
# Adding to a dictionary # Adding to a hashtable
$filledHash.Add("five",5) # $filledHash["five"] is set to 5 $filledHash.Add("five",5) # $filledHash["five"] is set to 5
$filledHash.Add("five",6) # exception "Item with key "five" has already been added" $filledHash.Add("five",6) # exception "Item with key "five" has already been added"
$filledHash["four"] = 4 # $filledHash["four"] is set to 4, running again does nothing $filledHash["four"] = 4 # $filledHash["four"] is set to 4, running again does nothing
# Remove keys from a dictionary with del # Remove keys from a hashtable
$filledHash.Remove("one") # Removes the key "one" from filled dict $filledHash.Remove("one") # Removes the key "one" from filled hashtable
#################################################### ####################################################