PDP-1 COMPUTER ELECTRICAL ENGINEERING DEPARTMENT MASSACHUSETTS INSTITUTE OF TECHNOLOGY CAMBRIDGE, MASSACHUSETTS 02139 PDP-9 TYPE JUSTIFIER 31 July 1972 u The type justifier accepts English text from Expensive Typewriter's text buffer, and reproduces it at any line length and page length on ET's alternate text buffer. The justifier has two modes of operation, fill mode and justify mode. In fill mode the right margin is approximately justified by moving words from one line to another, or by hyphenating words. Hyphenation data is obtained from the operator via the display. In justify mode the right margin is exactly aligned by stretching some of the spaces in the output line. The justifier has two modes of operation, normal mode and inverted indenting mode. All hyphens in the input text are assumed to mark compound words, and will be reproduced in the output. Any carriage returns immediately following a hyphen in a word are ignored. Any number of adjacent spaces (or characters treated as spaces) are treated as a single space. Backspace and unused concise codes are illegal. The program simulates tabs by spacing to the nearest imagined tab stop. Mode changes and special commands are indicated by the appearance of overbar, followed by other characters, in the input text. Justification The command overbar oj (".oj") puts the justifier in justify mode. The command overbar zj (".zj") puts the justifier in fill mode. Justify mode is the default. These commands may appear anywhere. Normal mode The justifier begins in normal mode, and may be set to normal mode by the appearance of overbar, n (".n") in the input text. In this mode lines begin at the left margin, and carriage return is treated as a space, except that a string of carriage returns is translated into the same number of carriage returns if they immediately precede a tab. Inverted indenting mode The justifier enters inverted indenting mode when the command ".i" is encountered. A counter .c is set to zero when the mode is entered. All input lines not preceded by two or more carriage returns are indented .c tab stops in the output. Each line in the input preceded by multiple carriage returns is preceded by the same number of carriage returns in the output. Also it is indented in the output by as many tabs as in the input, and .c is set to that number plus one. Quoted overbar The command overbar slash ("./") produces an overbar in the output. 2 i Quoted text The justification process may be suppressed, and input text copied directly onto the output, by the appearance of the command ".q". The command ".e" restores operation accord- ing to the previous justifying mode, and any other command except "./", ".g", ".oj", ".zj", ".oh", and ".zh" ends the quotation process and takes effect immediately. Centered lines The command ".c" causes the following line, up to the next carriage return, to be centered in the output text. The justifier then resumes its former justifying mode. Figures The command overbar, f, a decimal number, overbar, is a command to leave the indicated number of blank lines in the output for a figure. If there is not sufficient room on the current page, the space is left at the top of the following page, and justifying continues on the current page. If the "f" is omitted, no further text will be inserted before the figure, and, if there is not sufficient room on the current page, that page will terminate immediately. Setting parameters The command overbar, t, a decimal number, overbar, sets the tab spacing. The tab spacing is initially set to 3. The command overbar, l, a decimal number, overbar, sets the length of a justified line. It is initially 60. The command overbar, s, a decimal number, overbar, sets the output page size. If the number is zero, there will be no pagination. The page size is initally 56. The command ".p" starts a new page. Page numbers The command overbar, g, a decimal number, overbar, turns on page numbering. The current page number is set to the number specified. Page numbers appear on an extra line (one more than the number specified with the .s command) at the bottom of each page, right-justified. If the number in the command is zero, page numbering is turned off. It is initially off. Hyphenation The command ".oh" permits hyphenation in subsequent text. The command ".zh" prohibits hyphenation. Hyphenation is initially permitted. These commands may appear anywhere. If a word to by hyphenated is not found in the program's dictionary, the word will be displayed. To indicate that the 3 d word may be hyphenated between two letters, point the light pen at the + sign between the letters. The + sign will become an = sign. If an erroneous + was penned, pen the "oops" dot to start over. When all satisfactory hyphenation points have been marked, pen the "save" dot to insert the word in the dictionary, or the "forget" dot to use the hyphenation but not retain it. There will be no "save" dot if the dictionary is full. The dictionary is initially empty and can store approximately 600 words. Errors Errors cause self-explanatory printout on the typewriter. The page and line numbers given refer to the input text. 4