Shell Design Comparison

This is a friendly comparison of the syntax of different shells!

 

 

Print a string

oil shpp
source 
# oil requires quotes
echo 'hello world'

const name = 'world'
echo "hello $name"

# no single quotes
echo hello world

name = "world"
echo "hello ${name}"  # braces required
output 
hello world
hello world

hello world
hello world

Test if path exists

oil shpp
source 
if test --exists /bin/grep {
  echo 'file exists'
}

if path("/bin/grep").exists() {
  echo "file exists"
}
output 
file exists

file exists

Pipeline and Glob

oil shpp
source 
ls src* | sort -r | head -n 3

ls src* | sort -r | head -n 3
output 
src5
src4
src3

./src5
./src4
./src3

Read User Input

oil shpp
source 
echo hello | read --line

# _line starts with _, so it's a
# "register" mutated by the interpreter
echo "line: $_line"

# not sure how to feed stdin

line = read()
print("line: ", line)
output 
line: hello

line: [null]

Error Handling

oil shpp
source 
# TODO: Oil could expose strerror() like shpp

try zzz
if (_status === 127) {
  echo "zzz not installed"
}

try {
  zzz
} catch InvalidCmdException as ex {
  print("zzz not installed [msg: ", ex, "]")
}
output 
zzz not installed

zzz not installed [msg: zzz: No such file or directory]

Use Arrays

oil shpp
source 
const array1 = ['physics', 'chemistry', 1997, 2000]
const array2 = [1, 2, 3, 4, 5, 6, 7]

write -- "array1[0]: $[array1[0]]"

# TODO: Oil needs @[]
const slice = array2[1:5]
write -- "array2[1:5]" @slice

# use the word language: bare words, glob, brace expansion
const shell_style = %( README.md *.py {alice,bob}@example.com )
write -- @shell_style

array1 = ["physics", "chemistry", 1997, 2000];
array2 = [1, 2, 3, 4, 5, 6, 7 ];

print("array1[0]: ", array1[0])
print("array2[1:5]: ", array2[1:5])
output 
array1[0]: physics
array2[1:5]
2
3
4
5
README.md
bar.py
foo.py
alice@example.com
bob@example.com

array1[0]: physics
array2[1:5]: [2, 3, 4, 5]