Pander tables inside of knitr

Hadley Wickham opened my eyes that calling pander to generate nifty markdown tables inside of knitr requires a special chunk option, which bothersome extra step might be saved by updating pander a bit. So it’s done.

In a nutshell, whenever you call pander inside of a knitr document, instead of returning the markdown text to the standard output (as it used to happen), pander returns a knit_asis class object, which renders fine in the resulting document — without the double comment chars, so rendering the tables in HTML, pdf or other document formats just fine.

All those who might not like the new behaviour can of course disable it via panderOptions.

Quick demo:

No need to specify `results='asis'` anymore:

```{r}
## not to split tables
panderOptions('table.split.table', Inf)
## iris still rocks
pander(head(iris))
```

But you can if you wish:

```{r}
panderOptions('knitr.auto.asis', FALSE)
pander(head(iris))
```

```{r results='asis'}
pander(head(iris))
```

Results:

No need to specify `results='asis'` anymore:


```r
## not to split tables
panderOptions('table.split.table', Inf)
## iris still rocks
pander(head(iris))
```

-------------------------------------------------------------------
 Sepal.Length   Sepal.Width   Petal.Length   Petal.Width   Species 
-------------- ------------- -------------- ------------- ---------
     5.1            3.5           1.4            0.2       setosa  

     4.9             3            1.4            0.2       setosa  

     4.7            3.2           1.3            0.2       setosa  

     4.6            3.1           1.5            0.2       setosa  

      5             3.6           1.4            0.2       setosa  

     5.4            3.9           1.7            0.4       setosa  
-------------------------------------------------------------------

But you can if you wish:


```r
panderOptions('knitr.auto.asis', FALSE)
pander(head(iris))
```

```
## 
## -------------------------------------------------------------------
##  Sepal.Length   Sepal.Width   Petal.Length   Petal.Width   Species 
## -------------- ------------- -------------- ------------- ---------
##      5.1            3.5           1.4            0.2       setosa  
## 
##      4.9             3            1.4            0.2       setosa  
## 
##      4.7            3.2           1.3            0.2       setosa  
## 
##      4.6            3.1           1.5            0.2       setosa  
## 
##       5             3.6           1.4            0.2       setosa  
## 
##      5.4            3.9           1.7            0.4       setosa  
## -------------------------------------------------------------------
```

```r
pander(head(iris))
```

-------------------------------------------------------------------
 Sepal.Length   Sepal.Width   Petal.Length   Petal.Width   Species 
-------------- ------------- -------------- ------------- ---------
     5.1            3.5           1.4            0.2       setosa  

     4.9             3            1.4            0.2       setosa  

     4.7            3.2           1.3            0.2       setosa  

     4.6            3.1           1.5            0.2       setosa  

      5             3.6           1.4            0.2       setosa  

     5.4            3.9           1.7            0.4       setosa  
-------------------------------------------------------------------