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Add file extension to images
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| local known_exts = pandoc.List{".png", ".jpg", "jpeg"} | |
| if FORMAT:match 'tex' then | |
| known_exts = pandoc.List { | |
| ".pdf", ".png", ".jpg", ".mps", ".jpeg", ".jbig2", ".jb2" | |
| } | |
| elseif FORMAT:match 'html' then | |
| known_exts = pandoc.List { | |
| ".svg", ".png", ".jpg", ".jpeg", ".webp", ".gif" | |
| } | |
| end | |
| known_exts:extend(known_exts:map(string.upper)) | |
| local function add_extension(basename, ext) | |
| return basename .. (ext:sub(1,1) == '.' and ext or '.' .. ext) | |
| end | |
| local function file_exists(basename) | |
| return function (ext) | |
| local f = io.open(add_extension(basename, ext), 'r') | |
| return f and io.close(f) | |
| end | |
| end | |
| function Image (img) | |
| -- don't do anything if the image already has an extension | |
| if img.src:match '(%..+)$' then return end | |
| -- if the default extension has been given, use that; otherwise | |
| -- try all image extensions and use the first for which an image | |
| -- exists. | |
| img.src = add_extension( | |
| img.src, | |
| PANDOC_READER_OPTIONS.default_image_extension ~= '' | |
| and PANDOC_READER_OPTIONS.default_image_extension | |
| or (known_exts:find_if(file_exists(img.src)) or '') | |
| ) | |
| return img | |
| end |
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