149 lines
2.7 KiB
Plaintext
149 lines
2.7 KiB
Plaintext
====================================
|
|
While statements
|
|
====================================
|
|
|
|
while something happens; do
|
|
echo a
|
|
echo b
|
|
done
|
|
|
|
---
|
|
|
|
(program
|
|
(while_statement
|
|
(command (command_name (word)) (word))
|
|
(do_group
|
|
(command (command_name (word)) (word))
|
|
(command (command_name (word)) (word)))))
|
|
|
|
====================================
|
|
For statements
|
|
====================================
|
|
|
|
for a in 1 2 $(seq 5 10); do
|
|
echo $a
|
|
done
|
|
|
|
---
|
|
|
|
(program
|
|
(for_statement
|
|
(word)
|
|
(word)
|
|
(word)
|
|
(command_substitution (command (command_name (word)) (word) (word)))
|
|
(do_group
|
|
(command (command_name (word)) (simple_expansion (variable_name))))))
|
|
|
|
====================================
|
|
If statements
|
|
====================================
|
|
|
|
if cat some_file | grep -v ok; then
|
|
echo one
|
|
elif cat other_file | grep -v ok; then
|
|
echo two
|
|
else
|
|
exit
|
|
fi
|
|
|
|
---
|
|
|
|
(program
|
|
(if_statement
|
|
(pipeline
|
|
(command (command_name (word)) (word))
|
|
(command (command_name (word)) (word) (word)))
|
|
(command (command_name (word)) (word))
|
|
(elif_clause
|
|
(pipeline
|
|
(command (command_name (word)) (word))
|
|
(command (command_name (word)) (word) (word)))
|
|
(command (command_name (word)) (word)))
|
|
(else_clause
|
|
(command (command_name (word))))))
|
|
|
|
====================================
|
|
If statements with conditional expressions
|
|
====================================
|
|
|
|
if [ "$(uname)" == 'Darwin' ]; then
|
|
echo one
|
|
fi
|
|
|
|
---
|
|
|
|
(program
|
|
(if_statement
|
|
(bracket_command
|
|
(string (command_substitution (command (command_name (word)))))
|
|
(word)
|
|
(raw_string))
|
|
(command (command_name (word)) (word))))
|
|
|
|
====================================
|
|
Case statements
|
|
====================================
|
|
|
|
case "opt" in
|
|
a)
|
|
echo a
|
|
;;
|
|
|
|
b)
|
|
echo b
|
|
;;
|
|
esac
|
|
|
|
---
|
|
|
|
(program
|
|
(case_statement (string)
|
|
(case_item (word)
|
|
(command (command_name (word)) (word)))
|
|
(case_item (word)
|
|
(command (command_name (word)) (word)))))
|
|
|
|
===============================
|
|
Subshells
|
|
===============================
|
|
|
|
(
|
|
./start-server --port=80
|
|
) &
|
|
|
|
---
|
|
|
|
(program
|
|
(subshell (command (command_name (word)) (word))))
|
|
|
|
===============================
|
|
Function definitions
|
|
===============================
|
|
|
|
do_something() {
|
|
echo ok
|
|
}
|
|
|
|
function do_something_else() {
|
|
echo ok
|
|
}
|
|
|
|
function do_yet_another_thing {
|
|
echo ok
|
|
} 2>&1
|
|
|
|
---
|
|
|
|
(program
|
|
(function_definition
|
|
(word)
|
|
(compound_statement (command (command_name (word)) (word))))
|
|
(function_definition
|
|
(word)
|
|
(compound_statement (command (command_name (word)) (word))))
|
|
(function_definition
|
|
(word)
|
|
(compound_statement (command (command_name (word)) (word)))
|
|
(file_redirect (file_descriptor) (word))))
|