libharu:HPDFFont#get_x_height
「return NUM2INT(i);」は「return INT2NUM(i);」に修正
#!/usr/bin/env ruby require "hpdf" pdf = HPDFDoc.new page = pdf.add_page font = pdf.get_font("Helvetica", nil) p font.get_x_height pdf.use_jp_fonts pdf.use_jp_encodings font = pdf.get_font("MS-Mincyo", "90ms-RKSJ-H") p font.get_x_height
で、
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