What's the better (cleaner) way to ignore output in PowerShell?
What's the better (cleaner) way to ignore output in PowerShell?
What's the better (cleaner) way to ignore output in PowerShell?
Re: What's the better (cleaner) way to ignore output in PowerShell?
I just did some tests of the four options that I know about.
```
Measure-Command {$(1..1000) | Out-Null}
TotalMilliseconds : 76.211
Measure-Command {[Void]$(1..1000)}
TotalMilliseconds : 0.217
Measure-Command {$(1..1000) > $null}
TotalMilliseconds : 0.2478
Measure-Command {$null = $(1..1000)}
TotalMilliseconds : 0.2122
## Control, times vary from 0.21 to 0.24
Measure-Command {$(1..1000)}
TotalMilliseconds : 0.2141
```
So I would suggest that you use anything but `Out-Null` due to overhead. The next important thing, to me, would be readability. I kind of like redirecting to `$null` and setting equal to `$null` myself. I use to prefer casting to `[Void]`, but that may not be as understandable when glancing at code or for new users.
I guess I slightly prefer redirecting output to `$null`.
```
Do-Something > $null
```
**Edit**
After stej's comment again, I decided to do some more tests with pipelines to better isolate the overhead of trashing the output.
Here are some tests with a simple 1000 object pipeline.
```
## Control Pipeline
Measure-Command {$(1..1000) | ?{$_ -is [int]}}
TotalMilliseconds : 119.3823
## Out-Null
Measure-Command {$(1..1000) | ?{$_ -is [int]} | Out-Null}
TotalMilliseconds : 190.2193
## Redirect to $null
Measure-Command {$(1..1000) | ?{$_ -is [int]} > $null}
TotalMilliseconds : 119.7923
```
In this case, `Out-Null` has about a 60% overhead and `> $null` has about a 0.3% overhead.
**Addendum 2017-10-16:** I originally overlooked another option with `Out-Null`, the use of the `-inputObject` parameter. Using this the overhead seems to disappear, however the syntax is different:
```
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
```
And now for some tests with a simple 100 object pipeline.
```
## Control Pipeline
Measure-Command {$(1..100) | ?{$_ -is [int]}}
TotalMilliseconds : 12.3566
## Out-Null
Measure-Command {$(1..100) | ?{$_ -is [int]} | Out-Null}
TotalMilliseconds : 19.7357
## Redirect to $null
Measure
*(Réponse tronquée)*
```
Measure-Command {$(1..1000) | Out-Null}
TotalMilliseconds : 76.211
Measure-Command {[Void]$(1..1000)}
TotalMilliseconds : 0.217
Measure-Command {$(1..1000) > $null}
TotalMilliseconds : 0.2478
Measure-Command {$null = $(1..1000)}
TotalMilliseconds : 0.2122
## Control, times vary from 0.21 to 0.24
Measure-Command {$(1..1000)}
TotalMilliseconds : 0.2141
```
So I would suggest that you use anything but `Out-Null` due to overhead. The next important thing, to me, would be readability. I kind of like redirecting to `$null` and setting equal to `$null` myself. I use to prefer casting to `[Void]`, but that may not be as understandable when glancing at code or for new users.
I guess I slightly prefer redirecting output to `$null`.
```
Do-Something > $null
```
**Edit**
After stej's comment again, I decided to do some more tests with pipelines to better isolate the overhead of trashing the output.
Here are some tests with a simple 1000 object pipeline.
```
## Control Pipeline
Measure-Command {$(1..1000) | ?{$_ -is [int]}}
TotalMilliseconds : 119.3823
## Out-Null
Measure-Command {$(1..1000) | ?{$_ -is [int]} | Out-Null}
TotalMilliseconds : 190.2193
## Redirect to $null
Measure-Command {$(1..1000) | ?{$_ -is [int]} > $null}
TotalMilliseconds : 119.7923
```
In this case, `Out-Null` has about a 60% overhead and `> $null` has about a 0.3% overhead.
**Addendum 2017-10-16:** I originally overlooked another option with `Out-Null`, the use of the `-inputObject` parameter. Using this the overhead seems to disappear, however the syntax is different:
```
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
```
And now for some tests with a simple 100 object pipeline.
```
## Control Pipeline
Measure-Command {$(1..100) | ?{$_ -is [int]}}
TotalMilliseconds : 12.3566
## Out-Null
Measure-Command {$(1..100) | ?{$_ -is [int]} | Out-Null}
TotalMilliseconds : 19.7357
## Redirect to $null
Measure
*(Réponse tronquée)*