Function handler

src/environments/array.ts:803–838

(context, args)

        numArgs: 1,
    },
    handler(context, args) {
        // Since no types are specified above, the two possibilities are
        // - The argument is wrapped in {} or [], in which case Parser's
        //   parseGroup() returns an "ordgroup" wrapping some symbol node.
        // - The argument is a bare symbol node.
        const symNode = checkSymbolNodeType(args[0]);
        const colalign: AnyParseNode[] =
            symNode ? [args[0]] : assertNodeType(args[0], "ordgroup").body;
        const cols: AlignSpec[] = colalign.map(function(nde) {
            const node = assertSymbolNodeType(nde);
            const ca = node.text;
            if ("lcr".includes(ca)) {
                return {
                    type: "align",
                    align: ca,
                };
            } else if (ca === "|") {
                return {
                    type: "separator",
                    separator: "|",
                };
            } else if (ca === ":") {
                return {
                    type: "separator",
                    separator: ":",
                };
            }
            throw new ParseError("Unknown column alignment: " + ca, nde);
        });
        const res: Parameters<typeof parseArray>[1] = {
            cols,
            hskipBeforeAndAfter: true, // \@preamble in lttab.dtx
            maxNumCols: cols.length,
        };
        return parseArray(context.parser, res, dCellStyle(context.envName));
    },
    htmlBuilder,
    mathmlBuilder,
});