![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to ch1.r CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [CSRG BSD Unix] / 42BSD / ucb / lisp / lisplib / manual|
Return to ch1.r CVS log | Up to [CSRG BSD Unix] / 42BSD / ucb / lisp / lisplib / manual |
1.1 ! root 1: ! 2: ! 3: ! 4: ! 5: ! 6: ! 7: ! 8: CHAPTER 1 ! 9: ! 10: ! 11: FRANZ LISP ! 12: ! 13: ! 14: ! 15: ! 16: ! 17: ! 18: 1.1. FRANZ LISP[] was created as a tool to further ! 19: research in symbolic and algebraic manipulation, ! 20: artificial intelligence, and programming languages at ! 21: the University of California at Berkeley. Its roots ! 22: are in a PDP-11 Lisp system which originally came from ! 23: Harvard. As it grew it adopted features of Maclisp ! 24: and Lisp Machine Lisp which enables our work to be ! 25: shared with colleagues at the Laboratory for Computer ! 26: Science at M.I.T. Substantial compatibility with ! 27: other Lisp dialects (Interlisp, UCILisp, CMULisp) is ! 28: achieved by means of support packages and compiler ! 29: switches. The heart of FRANZ LISP is written almost ! 30: entirely in the programming language C. Of course, it ! 31: has been greatly extended by additions written in ! 32: Lisp. A small part is written in the assembly ! 33: language for the current host machines, VAXen and a ! 34: couple of flavors of 68000. Because FRANZ LISP is ! 35: written in C, it is relatively portable and easy to ! 36: comprehend. ! 37: ! 38: FRANZ LISP is capable of running large lisp pro- ! 39: grams in a timesharing environment, has facilities for ! 40: arrays and user defined structures, has a user con- ! 41: trolled reader with character and word macro capabil- ! 42: ities, and can interact directly with compiled Lisp, ! 43: C, Fortran, and Pascal code. ! 44: ! 45: This document is a reference manual for the FRANZ ! 46: LISP system. It is not a Lisp primer or introduction ! 47: to the language. Some parts will be of interest only ! 48: to those maintaining FRANZ LISP at their computer ! 49: site. This document is divided into four Movements. ! 50: In the first one we will attempt to describe the ! 51: language of FRANZ LISP precisely and completely as it ! 52: now stands (Opus 38.69, June 1983). In the second ! 53: Movement we will look at the reader, function types, ! 54: ____________________ ! 55: 9 []It is rumored that this name has something to do with ! 56: Franz Liszt [F_rants List] (1811-1886) a Hungarian composer ! 57: and keyboard virtuoso. These allegations have never been ! 58: proven. ! 59: ! 60: ! 61: ! 62: 9FRANZ LISP 1-1 ! 63: ! 64: ! 65: ! 66: ! 67: ! 68: ! 69: ! 70: FRANZ LISP 1-2 ! 71: ! 72: ! 73: arrays and exception handling. In the third Movement ! 74: we will look at several large support packages written ! 75: to help the FRANZ LISP user, namely the trace package, ! 76: compiler, fixit and stepping package. Finally the ! 77: fourth movement contains an index into the other ! 78: movements. In the rest of this chapter we shall exam- ! 79: ine the data types of FRANZ LISP. The conventions ! 80: used in the description of the FRANZ LISP functions ! 81: will be given in 1.3 -- it is very important that ! 82: these conventions are understood. ! 83: ! 84: ! 85: ! 86: 1.2. Data Types FRANZ LISP has fourteen data types. ! 87: In this section we shall look in detail at each type ! 88: and if a type is divisible we shall look inside it. ! 89: There is a Lisp function _t_y_p_e which will return the ! 90: type name of a lisp object. This is the official ! 91: FRANZ LISP name for that type and we will use this ! 92: name and this name only in the manual to avoid confus- ! 93: ing the reader. The types are listed in terms of ! 94: importance rather than alphabetically. ! 95: ! 96: ! 97: ! 98: 1.2.0. lispval This is the name we use to describe ! 99: any lisp object. The function _t_y_p_e will never ! 100: return `lispval'. ! 101: ! 102: ! 103: ! 104: 1.2.1. symbol This object corresponds to a variable ! 105: in most other programming languages. It may have a ! 106: value or may be `unbound'. A symbol may be _l_a_m_b_d_a ! 107: _b_o_u_n_d meaning that its current value is stored away ! 108: somewhere and the symbol is given a new value for ! 109: the duration of a certain context. When the Lisp ! 110: processor leaves that context, the symbol's ! 111: current value is thrown away and its old value is ! 112: restored. ! 113: 9 A symbol may also have a _f_u_n_c_t_i_o_n _b_i_n_d_i_n_g. This ! 114: function binding is static; it cannot be lambda ! 115: bound. Whenever the symbol is used in the func- ! 116: tional position of a Lisp expression the function ! 117: binding of the symbol is examined (see Chapter 4 ! 118: for more details on evaluation). ! 119: 9 A symbol may also have a _p_r_o_p_e_r_t_y _l_i_s_t, another ! 120: static data structure. The property list consists ! 121: of a list of an even number of elements, considered ! 122: to be grouped as pairs. The first element of the ! 123: pair is the _i_n_d_i_c_a_t_o_r the second the _v_a_l_u_e of that ! 124: indicator. ! 125: ! 126: ! 127: Printed: August 5, 1983 ! 128: ! 129: ! 130: ! 131: ! 132: ! 133: ! 134: ! 135: FRANZ LISP 1-3 ! 136: ! 137: ! 138: Each symbol has a print name (_p_n_a_m_e) which is how ! 139: this symbol is accessed from input and referred to ! 140: on (printed) output. ! 141: 9 A symbol also has a hashlink used to link symbols ! 142: together in the oblist -- this field is inaccessi- ! 143: ble to the lisp user. ! 144: 9 Symbols are created by the reader and by the func- ! 145: tions _c_o_n_c_a_t, _m_a_k_n_a_m and their derivatives. Most ! 146: symbols live on FRANZ LISP's sole _o_b_l_i_s_t, and ! 147: therefore two symbols with the same print name are ! 148: usually the exact same object (they are _e_q). Sym- ! 149: bols which are not on the oblist are said to be ! 150: _u_n_i_n_t_e_r_n_e_d. The function _m_a_k_n_a_m creates uninterned ! 151: symbols while _c_o_n_c_a_t creates _i_n_t_e_r_n_e_d ones. ! 152: ! 153: ! 154: 8 ____________________________________________________________ ! 155: Subpart name Get value Set value Type ! 156: ! 157: 8 ________________________________________________________________________________________________________________________ ! 158: value eval set lispval ! 159: setq ! 160: 8 ____________________________________________________________ ! 161: property plist setplist list or nil ! 162: list get putprop ! 163: defprop ! 164: 8 ____________________________________________________________ ! 165: function getd putd array, binary, list ! 166: binding def or nil ! 167: 8 ____________________________________________________________ ! 168: print name get_pname string ! 169: 8 ____________________________________________________________ ! 170: hash link ! 171: 8 ____________________________________________________________ ! 172: 7 |7|7|7|7|7|7|7|7|7|7|7|7|7| ! 173: ! 174: ! 175: ! 176: ! 177: ! 178: ! 179: ! 180: ! 181: ! 182: ! 183: ! 184: ! 185: |7|7|7|7|7|7|7|7|7|7|7|7|7| ! 186: ! 187: ! 188: ! 189: ! 190: ! 191: ! 192: ! 193: ! 194: ! 195: ! 196: ! 197: ! 198: |7|7|7|7|7|7|7|7|7|7|7|7|7| ! 199: ! 200: ! 201: ! 202: ! 203: ! 204: ! 205: ! 206: ! 207: ! 208: ! 209: ! 210: ! 211: |7|7|7|7|7|7|7|7|7|7|7|7|7| ! 212: ! 213: ! 214: ! 215: ! 216: ! 217: ! 218: ! 219: ! 220: ! 221: ! 222: ! 223: ! 224: |7|7|7|7|7|7|7|7|7|7|7|7|7| ! 225: ! 226: ! 227: ! 228: ! 229: ! 230: ! 231: ! 232: ! 233: ! 234: ! 235: ! 236: ! 237: ! 238: ! 239: ! 240: ! 241: ! 242: 1.2.2. list A list cell has two parts, called the ! 243: car and cdr. List cells are created by the func- ! 244: tion _c_o_n_s. ! 245: ! 246: ! 247: 8 ________________________________________________ ! 248: Subpart name Get value Set value Type ! 249: ! 250: 8 ________________________________________________________________________________________________ ! 251: car car rplaca lispval ! 252: 8 ________________________________________________ ! 253: cdr cdr rplacd lispval ! 254: 8 ________________________________________________ ! 255: 7 |8|7|7|7|7| ! 256: ! 257: ! 258: ! 259: 9 |8|7|7|7|7| ! 260: ! 261: ! 262: ! 263: 9 |8|7|7|7|7| ! 264: ! 265: ! 266: ! 267: 9 |8|7|7|7|7| ! 268: ! 269: ! 270: ! 271: 9 |8|7|7|7|7| ! 272: ! 273: ! 274: ! 275: ! 276: ! 277: 9 ! 278: ! 279: ! 280: ! 281: ! 282: ! 283: ! 284: 9 Printed: August 5, 1983 ! 285: ! 286: ! 287: ! 288: ! 289: ! 290: ! 291: ! 292: FRANZ LISP 1-4 ! 293: ! 294: ! 295: 1.2.3. binary This type acts as a function header ! 296: for machine coded functions. It has two parts, a ! 297: pointer to the start of the function and a symbol ! 298: whose print name describes the argument _d_i_s_c_i_p_l_i_n_e. ! 299: The discipline (if _l_a_m_b_d_a, _m_a_c_r_o or _n_l_a_m_b_d_a) deter- ! 300: mines whether the arguments to this function will ! 301: be evaluated by the caller before this function is ! 302: called. If the discipline is a string (specifi- ! 303: cally "_s_u_b_r_o_u_t_i_n_e", "_f_u_n_c_t_i_o_n", "_i_n_t_e_g_e_r-_f_u_n_c_t_i_o_n", ! 304: "_r_e_a_l-_f_u_n_c_t_i_o_n", "_c-_f_u_n_c_t_i_o_n", "_d_o_u_b_l_e-_c-_f_u_n_c_t_i_o_n", ! 305: or "_v_e_c_t_o_r-_c-_f_u_n_c_t_i_o_n" ) then this function is a ! 306: foreign subroutine or function (see 8.5 for more ! 307: details on this). Although the type of the _e_n_t_r_y ! 308: field of a binary type object is usually string or ! 309: other, the object pointed to is actually a sequence ! 310: of machine instructions. ! 311: Objects of type binary are created by _m_f_u_n_c_t_i_o_n, ! 312: _c_f_a_s_l, and _g_e_t_a_d_d_r_e_s_s. ! 313: ! 314: ! 315: 8 _________________________________________________________ ! 316: Subpart name Get value Set value Type ! 317: ! 318: 8 __________________________________________________________________________________________________________________ ! 319: entry getentry string or fixnum ! 320: 8 _________________________________________________________ ! 321: discipline getdisc putdisc symbol or fixnum ! 322: 8 _________________________________________________________ ! 323: 7 |8|7|7|7|7| ! 324: ! 325: ! 326: ! 327: 9 |8|7|7|7|7| ! 328: ! 329: ! 330: ! 331: 9 |8|7|7|7|7| ! 332: ! 333: ! 334: ! 335: 9 |8|7|7|7|7| ! 336: ! 337: ! 338: ! 339: 9 |8|7|7|7|7| ! 340: ! 341: ! 342: ! 343: ! 344: ! 345: 9 ! 346: ! 347: ! 348: 1.2.4. fixnum A fixnum is an integer constant in ! 349: the range -2[31] to 2[31]-1. Small fixnums (-1024 ! 350: to 1023) are stored in a special table so they ! 351: needn't be allocated each time one is needed. ! 352: ! 353: ! 354: ! 355: 1.2.5. flonum A flonum is a double precision real ! 356: number in the range +_2.9x10[-37] to +_1.7x10[38]. ! 357: There are approximately sixteen decimal digits of ! 358: precision. ! 359: ! 360: ! 361: ! 362: 1.2.6. bignum A bignum is an integer of potentially ! 363: unbounded size. When integer arithmetic exceeds ! 364: the limits of fixnums mentioned above, the calcula- ! 365: tion is automatically done with bignums. Should ! 366: calculation with bignums give a result which can be ! 367: represented as a fixnum, then the fixnum represen- ! 368: ! 369: ! 370: 9 ! 371: ! 372: 9 Printed: August 5, 1983 ! 373: ! 374: ! 375: ! 376: ! 377: ! 378: ! 379: ! 380: FRANZ LISP 1-5 ! 381: ! 382: ! 383: tation will be used[]. This contraction is known ! 384: as _i_n_t_e_g_e_r _n_o_r_m_a_l_i_z_a_t_i_o_n. Many Lisp functions ! 385: assume that integers are normalized. Bignums are ! 386: composed of a sequence of list cells and a cell ! 387: known as an sdot. The user should consider a big- ! 388: num structure indivisible and use functions such as ! 389: _h_a_i_p_a_r_t, and _b_i_g_n_u_m-_l_e_f_t_s_h_i_f_t to extract parts of ! 390: it. ! 391: ! 392: ! 393: ! 394: 1.2.7. string A string is a null terminated ! 395: sequence of characters. Most functions of symbols ! 396: which operate on the symbol's print name will also ! 397: work on strings. The default reader syntax is set ! 398: so that a sequence of characters surrounded by dou- ! 399: ble quotes is a string. ! 400: ! 401: ! 402: ! 403: 1.2.8. port A port is a structure which the system ! 404: I/O routines can reference to transfer data between ! 405: the Lisp system and external media. Unlike other ! 406: Lisp objects there are a very limited number of ! 407: ports (20). Ports are allocated by _i_n_f_i_l_e and _o_u_t_- ! 408: _f_i_l_e and deallocated by _c_l_o_s_e and _r_e_s_e_t_i_o. The ! 409: _p_r_i_n_t function prints a port as a percent sign fol- ! 410: lowed by the name of the file it is connected to ! 411: (if the port was opened by _f_i_l_e_o_p_e_n, _i_n_f_i_l_e, _o_r ! 412: _o_u_t_f_i_l_e). During initialization, FRANZ LISP binds ! 413: the symbol piport to a port attached to the stan- ! 414: dard input stream. This port prints as %$stdin. ! 415: There are ports connected to the standard output ! 416: and error streams, which print as %$stdout and ! 417: %$stderr. This is discussed in more detail at the ! 418: beginning of Chapter 5. ! 419: ! 420: ! 421: ! 422: 1.2.9. vector Vectors are indexed sequences of ! 423: data. They can be used to implement a notion of ! 424: user-defined types, via their associated property ! 425: list. They make hunks (see below) logically ! 426: unnecessary, although hunks are very efficiently ! 427: garbage collected. There is a second kind of vec- ! 428: tor, called an immediate-vector, which stores ! 429: binary data. The name that the function _t_y_p_e ! 430: ____________________ ! 431: 9 []The current algorithms for integer arithmetic opera- ! 432: tions will return (in certain cases) a result between +_2[30] ! 433: and 2[31] as a bignum although this could be represented as ! 434: a fixnum. ! 435: ! 436: ! 437: 9 Printed: August 5, 1983 ! 438: ! 439: ! 440: ! 441: ! 442: ! 443: ! 444: ! 445: FRANZ LISP 1-6 ! 446: ! 447: ! 448: returns for immediate-vectors is vectori. ! 449: Immediate-vectors could be used to implement ! 450: strings and block-flonum arrays, for example. Vec- ! 451: tors are discussed in chapter 9. The functions ! 452: _n_e_w-_v_e_c_t_o_r, and _v_e_c_t_o_r, can be used to create vec- ! 453: tors. ! 454: ! 455: ! 456: 8 ________________________________________________ ! 457: Subpart name Get value Set value Type ! 458: ! 459: 8 ________________________________________________________________________________________________ ! 460: datum[_i] vref vset lispval ! 461: 8 ________________________________________________ ! 462: property vprop vsetprop lispval ! 463: vputprop ! 464: 8 ________________________________________________ ! 465: size vsize - fixnum ! 466: 8 ________________________________________________ ! 467: 7 |7|7|7|7|7|7|7| ! 468: ! 469: ! 470: ! 471: ! 472: ! 473: ! 474: |7|7|7|7|7|7|7| ! 475: ! 476: ! 477: ! 478: ! 479: ! 480: ! 481: |7|7|7|7|7|7|7| ! 482: ! 483: ! 484: ! 485: ! 486: ! 487: ! 488: |7|7|7|7|7|7|7| ! 489: ! 490: ! 491: ! 492: ! 493: ! 494: ! 495: |7|7|7|7|7|7|7| ! 496: ! 497: ! 498: ! 499: ! 500: ! 501: ! 502: ! 503: ! 504: ! 505: ! 506: ! 507: 1.2.10. array Arrays are rather complicated types ! 508: and are fully described in Chapter 9. An array ! 509: consists of a block of contiguous data, a function ! 510: to access that data and auxiliary fields for use by ! 511: the accessing function. Since an array's accessing ! 512: function is created by the user, an array can have ! 513: any form the user chooses (e.g. n-dimensional, tri- ! 514: angular, or hash table). ! 515: Arrays are created by the function _m_a_r_r_a_y. ! 516: ! 517: ! 518: 8 _______________________________________________________________ ! 519: Subpart name Get value Set value Type ! 520: ! 521: 8 ______________________________________________________________________________________________________________________________ ! 522: access function getaccess putaccess binary, list ! 523: or symbol ! 524: 8 _______________________________________________________________ ! 525: auxiliary getaux putaux lispval ! 526: 8 _______________________________________________________________ ! 527: data arrayref replace block of contiguous ! 528: set lispval ! 529: 8 _______________________________________________________________ ! 530: length getlength putlength fixnum ! 531: 8 _______________________________________________________________ ! 532: delta getdelta putdelta fixnum ! 533: 8 _______________________________________________________________ ! 534: 7 |7|7|7|7|7|7|7|7|7|7|7| ! 535: ! 536: ! 537: ! 538: ! 539: ! 540: ! 541: ! 542: ! 543: ! 544: ! 545: |7|7|7|7|7|7|7|7|7|7|7| ! 546: ! 547: ! 548: ! 549: ! 550: ! 551: ! 552: ! 553: ! 554: ! 555: ! 556: |7|7|7|7|7|7|7|7|7|7|7| ! 557: ! 558: ! 559: ! 560: ! 561: ! 562: ! 563: ! 564: ! 565: ! 566: ! 567: |7|7|7|7|7|7|7|7|7|7|7| ! 568: ! 569: ! 570: ! 571: ! 572: ! 573: ! 574: ! 575: ! 576: ! 577: ! 578: |7|7|7|7|7|7|7|7|7|7|7| ! 579: ! 580: ! 581: ! 582: ! 583: ! 584: ! 585: ! 586: ! 587: ! 588: ! 589: ! 590: ! 591: ! 592: ! 593: ! 594: 1.2.11. value A value cell contains a pointer to a ! 595: lispval. This type is used mainly by arrays of ! 596: general lisp objects. Value cells are created with ! 597: the _p_t_r function. A value cell containing a ! 598: pointer to the symbol `foo' is printed as ! 599: ! 600: ! 601: Printed: August 5, 1983 ! 602: ! 603: ! 604: ! 605: ! 606: ! 607: ! 608: ! 609: FRANZ LISP 1-7 ! 610: ! 611: ! 612: `(ptr to)foo' ! 613: ! 614: ! 615: ! 616: 1.2.12. hunk A hunk is a vector of from 1 to 128 ! 617: lispvals. Once a hunk is created (by _h_u_n_k or ! 618: _m_a_k_h_u_n_k) it cannot grow or shrink. The access time ! 619: for an element of a hunk is slower than a list cell ! 620: element but faster than an array. Hunks are really ! 621: only allocated in sizes which are powers of two, ! 622: but can appear to the user to be any size in the 1 ! 623: to 128 range. Users of hunks must realize that ! 624: (_n_o_t (_a_t_o_m '_l_i_s_p_v_a_l)) will return true if _l_i_s_p_v_a_l ! 625: is a hunk. Most lisp systems do not have a direct ! 626: test for a list cell and instead use the above test ! 627: and assume that a true result means _l_i_s_p_v_a_l is a ! 628: list cell. In FRANZ LISP you can use _d_t_p_r to check ! 629: for a list cell. Although hunks are not list ! 630: cells, you can still access the first two hunk ele- ! 631: ments with _c_d_r and _c_a_r and you can access any hunk ! 632: element with _c_x_r[]. You can set the value of the ! 633: first two elements of a hunk with _r_p_l_a_c_d and _r_p_l_a_c_a ! 634: and you can set the value of any element of the ! 635: hunk with _r_p_l_a_c_x. A hunk is printed by printing ! 636: its contents surrounded by { and }. However a hunk ! 637: cannot be read in in this way in the standard lisp ! 638: system. It is easy to write a reader macro to do ! 639: this if desired. ! 640: ! 641: ! 642: ! 643: 1.2.13. other Occasionally, you can obtain a ! 644: pointer to storage not allocated by the lisp sys- ! 645: tem. One example of this is the entry field of ! 646: those FRANZ LISP functions written in C. Such ! 647: objects are classified as of type other. Foreign ! 648: functions which call malloc to allocate their own ! 649: space, may also inadvertantly create such objects. ! 650: The garbage collector is supposed to ignore such ! 651: objects. ! 652: ! 653: ! 654: ! 655: 1.3. Documentation The conventions used in the follow- ! 656: ing chapters were designed to give a great deal of ! 657: information in a brief space. The first line of a ! 658: function description contains the function name in ! 659: bold face and then lists the arguments, if any. The ! 660: ____________________ ! 661: 9 []In a hunk, the function _c_d_r references the first ele- ! 662: ment and _c_a_r the second. ! 663: ! 664: ! 665: ! 666: 9 Printed: August 5, 1983 ! 667: ! 668: ! 669: ! 670: ! 671: ! 672: ! 673: ! 674: FRANZ LISP 1-8 ! 675: ! 676: ! 677: arguments all have names which begin with a letter or ! 678: letters and an underscore. The letter(s) gives the ! 679: allowable type(s) for that argument according to this ! 680: table. ! 681: ! 682: ! 683: 8 _______________________________________________________ ! 684: Letter Allowable type(s) ! 685: ! 686: 8 ______________________________________________________________________________________________________________ ! 687: g any type ! 688: 8 _______________________________________________________ ! 689: s symbol (although nil may not be allowed) ! 690: 8 _______________________________________________________ ! 691: t string ! 692: 8 _______________________________________________________ ! 693: l list (although nil may be allowed) ! 694: 8 _______________________________________________________ ! 695: n number (fixnum, flonum, bignum) ! 696: 8 _______________________________________________________ ! 697: i integer (fixnum, bignum) ! 698: 8 _______________________________________________________ ! 699: x fixnum ! 700: 8 _______________________________________________________ ! 701: b bignum ! 702: 8 _______________________________________________________ ! 703: f flonum ! 704: 8 _______________________________________________________ ! 705: u function type (either binary or lambda body) ! 706: 8 _______________________________________________________ ! 707: y binary ! 708: 8 _______________________________________________________ ! 709: v vector ! 710: 8 _______________________________________________________ ! 711: V vectori ! 712: 8 _______________________________________________________ ! 713: a array ! 714: 8 _______________________________________________________ ! 715: e value ! 716: 8 _______________________________________________________ ! 717: p port (or nil) ! 718: 8 _______________________________________________________ ! 719: h hunk ! 720: 8 _______________________________________________________ ! 721: 7 |7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7| ! 722: ! 723: ! 724: ! 725: ! 726: ! 727: ! 728: ! 729: ! 730: ! 731: ! 732: ! 733: ! 734: ! 735: ! 736: ! 737: ! 738: ! 739: ! 740: ! 741: ! 742: ! 743: ! 744: ! 745: ! 746: ! 747: ! 748: |7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7| ! 749: ! 750: ! 751: ! 752: ! 753: ! 754: ! 755: ! 756: ! 757: ! 758: ! 759: ! 760: ! 761: ! 762: ! 763: ! 764: ! 765: ! 766: ! 767: ! 768: ! 769: ! 770: ! 771: ! 772: ! 773: ! 774: ! 775: |7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7|7| ! 776: ! 777: ! 778: ! 779: ! 780: ! 781: ! 782: ! 783: ! 784: ! 785: ! 786: ! 787: ! 788: ! 789: ! 790: ! 791: ! 792: ! 793: ! 794: ! 795: ! 796: ! 797: ! 798: ! 799: ! 800: ! 801: ! 802: ! 803: ! 804: ! 805: In the first line of a function description, those ! 806: arguments preceded by a quote mark are evaluated (usu- ! 807: ally before the function is called). The quoting con- ! 808: vention is used so that we can give a name to the ! 809: result of evaluating the argument and we can describe ! 810: the allowable types. If an argument is not quoted it ! 811: does not mean that that argument will not be ! 812: evaluated, but rather that if it is evaluated, the ! 813: time at which it is evaluated will be specifically ! 814: mentioned in the function description. Optional argu- ! 815: ments are surrounded by square brackets. An ellipsis ! 816: (...) means zero or more occurrences of an argument of ! 817: the directly preceding type. ! 818: ! 819: ! 820: ! 821: ! 822: ! 823: 9 Printed: August 5, 1983 ! 824: ! 825: ! 826:
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.