Add repl language tags for examples (#195)

docs/src/index.md

@@ -18,14 +18,14 @@ The interface is inspired by Erin Sheldon's
 
 `FITSIO.jl` can be installed using the built-in package manager
 
-```julia
+```julia-repl
 pkg> add FITSIO
 ```
 
 ## Usage
 
 To open an existing file for reading:
-```julia
+```julia-repl
 julia> using FITSIO
 
 julia> f = FITS("file.fits")
@@ -43,7 +43,7 @@ concatenated one after the other. The `FITS` object therefore is
 represented as a collection of these HDUs.
 
 Get information about the first HDU:
-```julia
+```julia-repl
 julia> f[1]
 File: file.fits
 HDU: 1
@@ -53,7 +53,7 @@ Datasize: (800, 800)
 ```
 
 Iterate over HDUs in the file:
-```julia
+```julia-repl
 julia> for hdu in f; println(typeof(hdu)); end
 FITSIO.ImageHDU
 FITSIO.TableHDU
@@ -63,7 +63,7 @@ FITSIO.TableHDU
 Each HDU can contain image data, or table data (either binary or
 ASCII-formatted). For image extensions, get the size of the image
 without reading it:
-```julia
+```julia-repl
 julia> ndims(f[1])
     2
 
@@ -76,15 +76,15 @@ julia> size(f[1], 2)
 
 
 Read an image from disk:
-```julia
+```julia-repl
 julia> data = read(f[1]);  # read an image from disk
 
 julia> data = read(f[1], :, 790:end);  # read just a subset of image
 ```
 
 
 Show info about a binary table:
-```julia
+```julia-repl
 julia> f[2]
 File: file.fits
 HDU: 2
@@ -97,19 +97,19 @@ Columns: Name  Size  Type    TFORM
 
 
 Read a column from the table:
-```julia
- julia> data = read(f[2], "col1")
+```julia-repl
+julia> data = read(f[2], "col1")
 ```
 
 Table HDUs implement the [Tables.jl](https://tables.juliadata.org/stable/) interface, so you can load them into other table types, like [DataFrames](https://dataframes.juliadata.org/stable/).
-```
+```julia-repl
 julia> df = DataFrame(f[2])
 ```
 Variable length columns are not supported by the Tables.jl interface, and `Tables` methods will ignore them.
 
 
 Read the entire header into memory and get values from it:
-```julia
+```julia-repl
 julia> header = read_header(f[1]);  # read the entire header from disk
 
 julia> length(header)  # total number of records in header
@@ -130,7 +130,7 @@ julia> get_comment(header, "NAXIS")  # get comment for a given keyword
 
 
 Read just a single header record without reading the entire header:
-```julia
+```julia-repl
 julia> read_key(f[1], 4)  # by position
 ("NAXIS1",800,"length of data axis 1")
 
@@ -140,22 +140,22 @@ julia> read_key(f[1], "NAXIS1")  # read by keyword
 
 
 Manipulate a header in memory:
-```julia
+```julia-repl
 julia> header["NEWKEY"] = 10  # change or add a keyword
 
 julia> set_comment!(header, "NEWKEY", "this is a comment")
 ```
 
 
 Close the file:
-```julia
+```julia-repl
 julia> close(f)
 ```
 (`FITS` objects are also closed automatically when garbage collected.)
 
 
 Open a new file for writing:
-```julia
+```julia-repl
 julia> f = FITS("newfile.fits", "w");
 ```
 The second argument can be `"r"` (read-only; default), `"r+"`
@@ -164,7 +164,7 @@ the same name is overwritten.
 
 
 Write an image to the file:
-```julia
+```julia-repl
 julia> data = reshape([1:100;], 5, 20)
 
 julia> write(f, data)  # Write a new image extension with the data
@@ -175,7 +175,7 @@ To write some header keywords in the new extension, pass a
 
 
 Overwrite image data in an existing file:
-```julia
+```julia-repl
 julia> f = FITS("newfile.fits", "r+")  # Reopen the file in read-write mode
 julia> data = reshape([101:200;], 5, 20)  # Prepare new image data
 julia> image_hdu = f[1]
@@ -184,7 +184,7 @@ julia> write(image_hdu, data)  # Overwrite the image
 
 
 Write a table to the file:
-```julia
+```julia-repl
 julia> data = Dict("col1"=>[1., 2., 3.], "col2"=>[1, 2, 3]);
 
 julia> write(f, data)  # write a new binary table to a new extension
@@ -193,7 +193,7 @@ julia> write(f, data)  # write a new binary table to a new extension
 !!! tip "Compressed storage"
     Setting the file extension to `.gz` will automatically use GZIP compression and save on storage space.
 
-    ```julia
+    ```julia-repl
     julia> FITS("abc.fits", "w") do f # save the image uncompressed
                write(f, ones(200,200))
            end
@@ -211,7 +211,7 @@ julia> write(f, data)  # write a new binary table to a new extension
 
     Alternately the compression algorithm might be specified in square brackets after the filename. Check the [CFITSIO website](https://heasarc.gsfc.nasa.gov/docs/software/fitsio/compression.html) for the details of this usage.
 
-    ```julia
+    ```julia-repl
     julia> FITS("abc.fits[compress R 100,100]", "w") do f # Rice algorithm with a 100 x 100 pixel tile size
                write(f, ones(200,200))
            end
@@ -221,4 +221,4 @@ julia> write(f, data)  # write a new binary table to a new extension
     ```
 
     !!! warn
-        Compression is "loss-less" for images with integer pixel values, and might be lossy for floating-point images. 
+        Compression is "loss-less" for images with integer pixel values, and might be lossy for floating-point images.