mirror of
https://github.com/tldr-pages/tldr.git
synced 2025-04-22 12:42:07 +02:00
6ea92d50ed
* Refresh page: - better grammar in descriptions - more examples - reorder examples * Fix the last example * Some rewordings Co-authored-by: Muhammad Falak R Wani <falakreyaz@gmail.com> * Rewording again * Fix errors * Change placeholders: - use an actual value in some placeholders - use generic placeholders instead of some actual values * Add note about supported operators * Update pages/common/expr.md Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com> * Fix quoting and simplify descriptions * Fix `index` description * Apply suggestions from code review --------- Co-authored-by: Muhammad Falak R Wani <falakreyaz@gmail.com> Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
32 lines
875 B
Markdown
32 lines
875 B
Markdown
# expr
|
|
|
|
> Evaluate expressions and manipulate strings.
|
|
> More information: <https://www.gnu.org/software/coreutils/expr>.
|
|
|
|
- Get the length of a specific string:
|
|
|
|
`expr length "{{string}}"`
|
|
|
|
- Get the substring of a string with a specific length:
|
|
|
|
`expr substr "{{string}}" {{from}} {{length}}`
|
|
|
|
- Match a specific substring against an anchored pattern:
|
|
|
|
`expr match "{{string}}" '{{pattern}}'`
|
|
|
|
- Get the first char position from a specific set in a string:
|
|
|
|
`expr index "{{string}}" "{{chars}}"`
|
|
|
|
- Calculate a specific mathematic expression:
|
|
|
|
`expr {{expression1}} {{+|-|*|/|%}} {{expression2}}`
|
|
|
|
- Get the first expression if its value is non-zero and not null otherwise get the second one:
|
|
|
|
`expr {{expression1}} \| {{expression2}}`
|
|
|
|
- Get the first expression if both expressions are non-zero and not null otherwise get zero:
|
|
|
|
`expr {{expression1}} \& {{expression2}}`
|