Library functions#

The method names are exactly the sames as the Go names, with a few changes:

The first letter is always a lowercase letter: The method FormatParagraph is called formatParagraph in JavaScript.
When the method name (or a variable name) starts with an upper case word such as PDF, it is now lowercase. Example: the backend document's variable PDFWriter can be accessed via pdfWriter (notice the uppercase 'W').

baseline-pdf#

The library is loaded with require("bag:baseline").

JS library function	Go equivalent	Info
`new(filename)`	`pdf.NewPDFWriter(w)`	The argument to `new()` is converted to a `io.Writer` internally.
`string(string)`	`pdf.String()`	The argument is converted to a PDF string.
`serialize(arg)`	`pdf.Serialize(arg)`	Creates a string representation of the argument which is suitable to write in the PDF file. For examples arrays are converted to `[....]`.

backend document#

The library is loaded with require("bag:backend/document").

JS library function	Go equivalent	Info
`document(filename)`	`document.NewDocument(w)`	The argument to `document()` is converted to a `io.Writer` internally.

Example code:

const bag = require("bag:backend/bag");
const document = require("bag:backend/document");

const doc = new document.document("out.pdf");

const p1 = doc.newPage();
p1.width = bag.mustSP("21cm");
p1.height = bag.mustSP("29.7cm");
p1.shipout() ;


doc.finish();

backend bag#

The library is loaded with require("bag:backend/bag")

JS library function	Go equivalent	Info
`mustSP(arg)`	`MustSP(arg)`
`sp(arg)`	`SP`
`factor`	`Factor`
`scaledPointFromFloat()`	`ScaledPointFromFloat()`
`max()`	`Max()`
`min()`	`Min()`
`maxSP()`	`MaxSP()`
`multiplyFloat()`	`MultiplyFloat()`

backend color#

The library is loaded with require("bag:backend/color")

To initialize a new color use new:

const mycolor = new color.color()
mycolor.space = color.colorRGB
mycolor.r = 0.03
mycolor.g = 0.37
mycolor.b = 1

or use a constructor like

const mycolor = new color.color({ space: color.colorRGB, r: 0.03, g:0.37, b: 1 })

JS library constants	Go equivalent	Info
`colorNone`	`ColorNone`
`colorRGB`	`ColorRGB`
`colorCMYK`	`ColorCMYK`
`colorGray`	`ColorGray`
`colorSpotcolor`	`ColorSpotcolor`

See the color section in the manual for a list of methods.

backend font#

The library is loaded with require("bag:backend/font")

JS library function	Go equivalent	Info
`newFont(face,size)`	`NewFont()`	Create an initialized Font instance
`new Font()`	`&Font{}`	Create a new (empty) Font instance

Load a face and convert it to a font with the document backend library:

const face = doc.loadFace("CrimsonPro-Regular.ttf", 0);
const fnt = font.newFont(face, bag.mustSP("12pt"));

backend image#

The library is loaded with require("bag:backend/image")

JS library function	Go equivalent	Info
`new image()`	`Image{}`	Return empty Image struct

Normally the image struct should be created with a call to doc.createImage():

const doc = new document.document("out.pdf");
const img = doc.pdfWriter.loadImageFile("ocean.pdf");
const i = doc.createImage(img,1,"/MediaBox");
imageNode = node.newImage();
imageNode.img = i;
imageNode.width = bag.mustSP("4cm");
imageNode.height = bag.mustSP("4cm");

backend lang#

The library is loaded with require("bag:backend/lang")

JS library function	Go equivalent	Info
`loadPatternFile(filename)`	`LoadPatternFile(filename)`	Initialize language from hyphenation pattern file.
`new lang()`	`Lang{}`	Return empty Lang struct

backend node#

The library is loaded with require("bag:backend/node")

JS library function	Go equivalent	Info
`boxit()`	`Boxit()`
`copyList()`	`CopyList()`
`dimensions()`	`Dimensions()`
`hpack()`	`Hpack()`
`hpackTo()`	`HpackTo()`
`hpackToWithEnd()`	`HpackToWithEnd()`
`insertAfter()`	`InsertAfter()`
`insertBefore()`	`InsertBefore()`
`newDisc()`	`NewDisc()`
`newGlue()`	`NewGlue()`
`newGlyph()`	`NewGlyph()`
`newHList()`	`NewHList()`
`newImage()`	`NewImage()`
`newKern()`	`NewKern()`
`newPenalty()`	`NewPenalty()`
`newRule()`	`NewRule()`
`newStartStop()`	`NewStartStop()`
`newVList()`	`NewVList()`
`tail()`	`Tail()`
`vpack()`	`Vpack()`
`debug()`	`Debug()`

frontend#

The library is loaded with require("bag:frontend")

JS library function	Go equivalent	Info
`new(filename)`	`New(filename)`
`getLanguage(name)`	`GetLanguage(name)`
`new fontSource(args)`	`FontSource{}`	Return a FontSource struct

new fe.fontSource( {location: "FiraSans-Regular.otf", fontFeatures: ["smcp"] })

JS library constants	Go equivalent	Info
`fontStyleNormal`	`FontStyleNormal`
`fontStyleItalic`	`FontStyleItalic`
`fontStyleOblique`	`FontStyleOblique`
`fontWeight100`	`FontWeight100`
`fontWeight200`	`FontWeight200`
`fontWeight300`	`FontWeight300`
`fontWeight400`	`FontWeight400`
`fontWeight500`	`FontWeight500`
`fontWeight600`	`FontWeight600`
`fontWeight700`	`FontWeight700`
`fontWeight800`	`FontWeight800`
`fontWeight900`	`FontWeight900`
`settingTextDecorationLine`	`SettingTextDecorationLine`
`settingBox`	`SettingBox`
`settingBackgroundColor`	`SettingBackgroundColor`
`settingBorderBottomWidth`	`SettingBorderBottomWidth`
`settingBorderLeftWidth`	`SettingBorderLeftWidth`
`settingBorderRightWidth`	`SettingBorderRightWidth`
`settingBorderTopWidth`	`SettingBorderTopWidth`
`settingBorderBottomColor`	`SettingBorderBottomColor`
`settingBorderLeftColor`	`SettingBorderLeftColor`
`settingBorderRightColor`	`SettingBorderRightColor`
`settingBorderTopColor`	`SettingBorderTopColor`
`settingBorderBottomStyle`	`SettingBorderBottomStyle`
`settingBorderLeftStyle`	`SettingBorderLeftStyle`
`settingBorderRightStyle`	`SettingBorderRightStyle`
`settingBorderTopStyle`	`SettingBorderTopStyle`
`settingBorderTopLeftRadius`	`SettingBorderTopLeftRadius`
`settingBorderTopRightRadius`	`SettingBorderTopRightRadius`
`settingBorderBottomLeftRadius`	`SettingBorderBottomLeftRadius`
`settingBorderBottomRightRadius`	`SettingBorderBottomRightRadius`
`settingColor`	`SettingColor`
`settingDebug`	`SettingDebug`
`settingFontExpansion`	`SettingFontExpansion`
`settingFontFamily`	`SettingFontFamily`
`settingFontWeight`	`SettingFontWeight`
`settingHAlign`	`SettingHAlign`
`settingHangingPunctuation`	`SettingHangingPunctuation`
`settingHeight`	`SettingHeight`
`settingHyperlink`	`SettingHyperlink`
`settingIndentLeft`	`SettingIndentLeft`
`settingIndentLeftRows`	`SettingIndentLeftRows`
`settingLeading`	`SettingLeading`
`settingMarginBottom`	`SettingMarginBottom`
`settingMarginLeft`	`SettingMarginLeft`
`settingMarginRight`	`SettingMarginRight`
`settingMarginTop`	`SettingMarginTop`
`settingOpenTypeFeature`	`SettingOpenTypeFeature`
`settingPaddingBottom`	`SettingPaddingBottom`
`settingPaddingLeft`	`SettingPaddingLeft`
`settingPaddingRight`	`SettingPaddingRight`
`settingPaddingTop`	`SettingPaddingTop`
`settingPrepend`	`SettingPrepend`
`settingPreserveWhitespace`	`SettingPreserveWhitespace`
`settingSize`	`SettingSize`
`settingStyle`	`SettingStyle`
`settingTabSizeSpaces`	`SettingTabSizeSpaces`
`settingTabSize`	`SettingTabSize`
`settingTextDecorationLine`	`SettingTextDecorationLine`
`settingWidth`	`SettingWidth`
`settingVAlign`	`SettingVAlign`
`settingYOffset`	`SettingYOffset`

harfbuzz#

The library is loaded with require("bag:harfbuzz")

JS library function	Go equivalent	Info
`newBuffer()`	`NewBuffer()`
`features(array)`		Convert the array of strings to harfbuzz features

XML/XSLT#

The library is loaded with require("xml")

JS library function	Go equivalent	Info
`newParser()`	`NewParser()`

xpath = require("xpath")
const mf = xpath.newParser("myfile.xml");
const seq = mf.evaluate("/log/*");

for (const itm of seq) {
    console.log(itm);
}

See pkg.go.dev/github.com/speedata/goxpath and pkg.go.dev/github.com/speedata/goxml for documentation hints.