Skip to content
Merged
Changes from all commits
Commits
File filter

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 3 additions & 1 deletion ebook/en/content/009-bash-conditional-expressions.md
Original file line number Diff line number Diff line change
Expand Up @@ -85,9 +85,11 @@ Here is a list of the most popular Bash conditional expressions. You do not have
* True if the shell variable varname is set (has been assigned a value).

```bash
[[ -v ${varname} ]]
[[ -v varname ]]
```

> Here, `varname` is the name of the variable. The `-v` operator expects a variable name as an argument rather than a value, so if you pass `${varname}` instead of `varname`, the expression will return false.

True if the length of the string is zero.

```bash
Expand Down