diff options
| -rw-r--r-- | bash.html.markdown | 14 | 
1 files changed, 14 insertions, 0 deletions
| diff --git a/bash.html.markdown b/bash.html.markdown index c2c3e3f1..a62bd167 100644 --- a/bash.html.markdown +++ b/bash.html.markdown @@ -11,6 +11,7 @@ contributors:      - ["Rahil Momin", "https://github.com/iamrahil"]      - ["Gregrory Kielian", "https://github.com/gskielian"]      - ["Etan Reisner", "https://github.com/deryni"] +    - ["Jonathan Wang", "https://github.com/Jonathansw"                       ]  filename: LearnBash.sh  --- @@ -54,6 +55,13 @@ echo '$Variable'  # its name without $. If you want to use the variable's value, you should use $.  # Note that ' (single quote) won't expand the variables! +# Parameter expansion ${ }: +echo ${Variable} +# This is a simple usage of parameter expansion +# Parameter Expansion gets a value from a variable.  It "expands" or prints the value +# During the expansion time the value or parameter are able to be modified +# Below are other modifications that add onto this expansion +  # String substitution in variables  echo ${Variable/Some/A}  # This will substitute the first occurrence of "Some" with "A" @@ -68,6 +76,12 @@ echo ${Foo:-"DefaultValueIfFooIsMissingOrEmpty"}  # This works for null (Foo=) and empty string (Foo=""); zero (Foo=0) returns 0.  # Note that it only returns default value and doesn't change variable value. +# Brace Expansion { } +# Used to generate arbitrary strings +echo {1..10} +echo {a..z} +# This will output the range from the start value to the end value +  # Builtin variables:  # There are some useful builtin variables, like  echo "Last program's return value: $?" | 
