Met English
Encyclopedia
Met English Language was an early computer language used by the Metropolitan Life Insurance Company
Metropolitan Life Insurance Company
MetLife, Inc. is the holding corporation for the Metropolitan Life Insurance Company, or MetLife, for short, and its affiliates. MetLife is among the largest global providers of insurance, annuities, and employee benefit programs, with 90 million customers in over 60 countries...

 (MetLife). It enabled MetLife to establish itself as a strong technology company in the early days of commercial computing. It has now been retired and is no longer in use.

Language characteristics

Met English was a Fortran
Fortran
Fortran is a general-purpose, procedural, imperative programming language that is especially suited to numeric computation and scientific computing...

-like language. Two of its most peculiar characteristics were bytes and fields of variable "bitness" or length in bits, and the use of self-modifying code
Self-modifying code
In computer science, self-modifying code is code that alters its own instructions while it is executing - usually to reduce the instruction path length and improve performance or simply to reduce otherwise repetitively similar code, thus simplifying maintenance...

 (conditional branches were implemented by modifying the target address of branch instructions in memory). The language was very rich in mathematical functions, especially those useful to the insurance
Insurance
In law and economics, insurance is a form of risk management primarily used to hedge against the risk of a contingent, uncertain loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for payment. An insurer is a company selling the...

 industry. It was verbose with syntax like "ADD (A FIELDA) TO (B FIELDB) PUTTING RESULT INTO (ANSWER)".

Impact

Met English was used to write some of the most complex business systems of the 1960s. It remained the primary language used by MetLife in the 1970s, but was gradually phased out after the company standardized on IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

 hardware and software in the mid-1980s. Met English systems continued to run in the company (with a new IBM compiler that generated IBM assembler language) well into the 1990s. MEL was (almost) entirely retired as part of the preparation for Y2K.

The UNIVAC Compiler

The UNIVAC
UNIVAC
UNIVAC is the name of a business unit and division of the Remington Rand company formed by the 1950 purchase of the Eckert-Mauchly Computer Corporation, founded four years earlier by ENIAC inventors J. Presper Eckert and John Mauchly, and the associated line of computers which continues to this day...

 English Language compiler
Compiler
A compiler is a computer program that transforms source code written in a programming language into another computer language...

 was the first one produced at MetLife, in 1959. (Other sources indicate 1957.) Its chief value was in the experience gained in the use of the language and in implementing the compiler program. This initial effort made the later H-800 compilers more efficient by allowing improvement attributable to hindsight. The UNIVAC Compiler was used as late as 1964.

The Compromise Compiler

The Compromise English Language Compiler compiled on UNIVAC II but produced H-800 coding. This approach allowed MetLife to have a compiling system in existence for the H-800 almost as soon as the machines were installed. All production work on the Honeywell
Honeywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....

 systems was processed through the Compromise Compiler until the summer of 1963.

The Hybrid Compiler

The Hybrid Compiler was an interim device midway between the Compromise and the H-800 Compilers. The first half of the compilation was done on the H-800 computer using completed sections of the H-800 Compiler; the remainder was done on the Compromise Compiler. Advantages were conservation of machine time, better diagnostics and some liberalizing of the language rules.

The H-800 Compiler

The H-800 compiler, also known as HLOC, ran exclusively on the Honeywell System. Its usage became standard practice in 1964. It made possible additional language facilities.

The ELCA Compiler

The ELCA compiler gradually replaced HLOC during the years 1975-1977. It ran faster and generated better code and incorporated many useful language extensions. It had the option to generate assembly language (GMAP) which could be processed on Honeywell Series 66 machines.

The Emulator

In the 1980s MetLife "migrated" Met English programs from Honeywell hardware to IBM. (IBM hardware had been in use for COBOL
COBOL
COBOL is one of the oldest programming languages. Its name is an acronym for COmmon Business-Oriented Language, defining its primary domain in business, finance, and administrative systems for companies and governments....

programs for some time.) The Emulator read Honeywell machine code and interpreted each instruction on an MVS system. Some emulated programs were quite slow and this was not pursued as a long term solution.

The ELCA2 Compiler

MetLife developed a new compiler that generated IBM assembler code. The standard IBM assembler generated machine code from that. Versions of this compiler were used until the language was retired.
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