1. Introduction: Why Lisp ?
If you think the greatest pleasure in programming comes from getting a lot done with code that simply and clearly expresses your intention, then programming in Common Lisp is likely to be about the most fun you can have with a computer. You'll get more done, faster, using it than you would using pretty much any other language.
If you've used Lisp in the past, you may have ideas about what "Lisp" is that have little to do with Common Lisp . While Common Lisp supplanted most of the dialects it's descended from, it isn't the only remaining Lisp dialect, and depending on where and when you were exposed to Lisp, you may very well have learned one of these other dialects.
Other than Common Lisp , the one general-purpose Lisp dialect that still has an active user community is Scheme. Common Lisp borrowed a few important features from Scheme but never intended to replace it.
Originally designed at M.I.T., where it was quickly put to use as a teaching language for undergraduate computer science courses, Scheme has always been aimed at a different language niche than Common Lisp ,. In particular, Scheme's designers have focused on keeping the core language as small and as simple as possible. This has obvious benefits for a teaching language and also for programming language researchers who like to be able to formally prove things about languages.
2. Syntax and Symantics
i) Lisp is syntax is quite different from the other languages. In lisp everything is enclosed between parenthesis("(",")").
ii) The evaluation rule for function call forms is simple: evaluate the remaining elements of the list as Lisp forms and pass the resulting values to the named function. This rule obviously places some additional syntactic constraints on a function call form: all the elements of the list after the first must themselves be well-formed Lisp forms. In other words, the basic syntax of a function call form is as follows, where each of the arguments is itself a Lisp form:
(function-name argument*)
Thus, the following expression is evaluated by first evaluating 1, then evaluating 2, and then passing the resulting values to the + function, which returns 3:
(+ 1 2) so,if you want to evaluate value of 2*3+4 you should give in lisp like this (+ * 2 3 4).
If you think the greatest pleasure in programming comes from getting a lot done with code that simply and clearly expresses your intention, then programming in Common Lisp is likely to be about the most fun you can have with a computer. You'll get more done, faster, using it than you would using pretty much any other language.
If you've used Lisp in the past, you may have ideas about what "Lisp" is that have little to do with Common Lisp . While Common Lisp supplanted most of the dialects it's descended from, it isn't the only remaining Lisp dialect, and depending on where and when you were exposed to Lisp, you may very well have learned one of these other dialects.
Other than Common Lisp , the one general-purpose Lisp dialect that still has an active user community is Scheme. Common Lisp borrowed a few important features from Scheme but never intended to replace it.
Originally designed at M.I.T., where it was quickly put to use as a teaching language for undergraduate computer science courses, Scheme has always been aimed at a different language niche than Common Lisp ,. In particular, Scheme's designers have focused on keeping the core language as small and as simple as possible. This has obvious benefits for a teaching language and also for programming language researchers who like to be able to formally prove things about languages.
2. Syntax and Symantics
i) Lisp is syntax is quite different from the other languages. In lisp everything is enclosed between parenthesis("(",")").
ii) The evaluation rule for function call forms is simple: evaluate the remaining elements of the list as Lisp forms and pass the resulting values to the named function. This rule obviously places some additional syntactic constraints on a function call form: all the elements of the list after the first must themselves be well-formed Lisp forms. In other words, the basic syntax of a function call form is as follows, where each of the arguments is itself a Lisp form:
(function-name argument*)
Thus, the following expression is evaluated by first evaluating 1, then evaluating 2, and then passing the resulting values to the + function, which returns 3:
(+ 1 2) so,if you want to evaluate value of 2*3+4 you should give in lisp like this (+ * 2 3 4).
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