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Note to prefer $() over ``, and update single example to conform #100

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Note to prefer $() over ``, and update single example to conform #100

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dd7d40a
Note to prefer $() over ``, and update single example to conform
mlcurry Oct 20, 2019
caf35ca
Change order of examples for nested commands to prefer $()
matthewcurry Oct 27, 2019
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12 changes: 7 additions & 5 deletions README.md
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Expand Up @@ -289,16 +289,18 @@ echo {00..8..2} # 00 02 04 06 08

## Command substitution

Command substitution allow us to evaluate a command and substitute its value into another command or variable assignment. Command substitution is performed when a command is enclosed by ``` `` ``` or `$()`. For example, we can use it as follows:
Command substitution allow us to evaluate a command and substitute its value into another command or variable assignment. Command substitution is performed when a command is enclosed by `$()` or ``` `` ```. For example, we can use it as follows:

```bash
now=`date +%T`
# or
now=$(date +%T)
# or
now=`date +%T`

echo $now # 19:08:26
```

Many prefer `$()` over ``` `` ``` because the latter cannot be nested, and the back-tick character is easy to mistake for an apostrophe in print.

## Arithmetic expansion

In bash we are free to do any arithmetical operations. But the expression must enclosed by `$(( ))` The format for arithmetic expansions is:
Expand Down Expand Up @@ -641,9 +643,9 @@ Sometimes `if..else` statements are not enough to do what we want to do. In this
Look at the example below:

```bash
if [[ `uname` == "Adam" ]]; then
if [[ $(uname) == "Adam" ]]; then
echo "Do not eat an apple!"
elif [[ `uname` == "Eva" ]]; then
elif [[ $(uname) == "Eva" ]]; then
echo "Do not take an apple!"
else
echo "Apples are delicious!"
Expand Down