Dartmouth ALGOL 30
Encyclopedia
Dartmouth ALGOL 30 was an implementation, firstly of ALGOL 58
, then of ALGOL 60
for the LGP-30
at Dartmouth College
, hence the name.
Since the limited size of the LGP-30
precluded a full implementation of ALGOL 60, certain of its features (arrays called by value, own arrays, strings, variable array bounds, and recursion) were omitted; but the implementors did include parameters called by name, using "thunks" (Ingerman, 1961; Irons and Wally Feurzeig
, 1961), and integer labels. They dubbed their work ALGOL 30, since it was for the LGP-30 (Kurtz, 1962a, Feb., 1962b, Mar.). From this project emerged a small group of undergraduate students who were well equipped to perform further work in the development of computer languages. For instance, one student (Steve Garland) discovered that compound statements and blocks could be included in the Samelson and Bauer scanning algorithm. This simple fact was not published until some years later. (The author has been unable to identify the source that he clearly remembers; the closest is Gries, 1968.)
"The ALGOL 30 system suffered one defect that hindered its wide use as a student-oriented language: it was a two-pass system. The intermediate code was similar to relocatable binary, but had to be punched onto paper tape. Compilations could be "batched," but the delays between presenting the source code tape and the final execution were too great to allow widespread student use. It was clear that a "load-and-go" system was needed. Thus was born SCALP, a Self Contained ALgol Processor (Kurtz, 1962c, Oct.)."
ALGOL 58
ALGOL 58, originally known as IAL, is one of the family of ALGOL computer programming languages. It was an early compromise design soon superseded by ALGOL 60...
, then of ALGOL 60
ALGOL 60
ALGOL 60 is a member of the ALGOL family of computer programming languages. It gave rise to many other programming languages, including BCPL, B, Pascal, Simula, C, and many others. ALGOL 58 introduced code blocks and the begin and end pairs for delimiting them...
for the LGP-30
LGP-30
The LGP-30, standing for Librascope General Purpose and then Librascope General Precision, was an early off-the-shelf computer. It was manufactured by the Librascope company of Glendale, California , and sold and serviced by the Royal Precision Electronic Computer Company, a joint venture with the...
at Dartmouth College
Dartmouth College
Dartmouth College is a private, Ivy League university in Hanover, New Hampshire, United States. The institution comprises a liberal arts college, Dartmouth Medical School, Thayer School of Engineering, and the Tuck School of Business, as well as 19 graduate programs in the arts and sciences...
, hence the name.
Since the limited size of the LGP-30
LGP-30
The LGP-30, standing for Librascope General Purpose and then Librascope General Precision, was an early off-the-shelf computer. It was manufactured by the Librascope company of Glendale, California , and sold and serviced by the Royal Precision Electronic Computer Company, a joint venture with the...
precluded a full implementation of ALGOL 60, certain of its features (arrays called by value, own arrays, strings, variable array bounds, and recursion) were omitted; but the implementors did include parameters called by name, using "thunks" (Ingerman, 1961; Irons and Wally Feurzeig
Wally Feurzeig
Wally Feurzeig is an inventor of the LOGO programming language, and a well-known researcher in Artificial Intelligence.During the early 1960s, BBN had become a major center of computer science research and innovative applications...
, 1961), and integer labels. They dubbed their work ALGOL 30, since it was for the LGP-30 (Kurtz, 1962a, Feb., 1962b, Mar.). From this project emerged a small group of undergraduate students who were well equipped to perform further work in the development of computer languages. For instance, one student (Steve Garland) discovered that compound statements and blocks could be included in the Samelson and Bauer scanning algorithm. This simple fact was not published until some years later. (The author has been unable to identify the source that he clearly remembers; the closest is Gries, 1968.)
"The ALGOL 30 system suffered one defect that hindered its wide use as a student-oriented language: it was a two-pass system. The intermediate code was similar to relocatable binary, but had to be punched onto paper tape. Compilations could be "batched," but the delays between presenting the source code tape and the final execution were too great to allow widespread student use. It was clear that a "load-and-go" system was needed. Thus was born SCALP, a Self Contained ALgol Processor (Kurtz, 1962c, Oct.)."