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Changed name format.

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Lewis Van Winkle
2016-02-11 14:24:50 -06:00
parent 683de28d08
commit df92386cc9
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README.md
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@@ -1,11 +1,11 @@
#TINYEXPR #TinyExpr
TINYEXPR is a very small recursive descent parser and evaluation engine for TinyExpr is a very small recursive descent parser and evaluation engine for
math expressions. It's handy when you want to add the ability to evaluation math expressions. It's handy when you want to add the ability to evaluation
math expressions at runtime without adding a bunch of cruft to you project. math expressions at runtime without adding a bunch of cruft to you project.
In addition to the standard math operators and precedence, TINYEXPR also supports In addition to the standard math operators and precedence, TinyExpr also supports
the standard C math functions and runtime binding of variables. the standard C math functions and runtime binding of variables.
##Features ##Features
@@ -32,7 +32,7 @@ Here is a minimal example to evaluate an expression at runtime.
##Usage ##Usage
TINYEXPR defines only four functions: TinyExpr defines only four functions:
```C ```C
double te_interp(const char *expression, int *error); double te_interp(const char *expression, int *error);
@@ -192,9 +192,9 @@ and return the result of the expression.
##Speed ##Speed
TINYEXPR is pretty fast compared to C when the expression is short, when the TinyExpr is pretty fast compared to C when the expression is short, when the
expression does hard calculations (e.g. exponentiation), and when some of the expression does hard calculations (e.g. exponentiation), and when some of the
work can be simplified by `te_compile()`. TINYEXPR is slow compared to C when the work can be simplified by `te_compile()`. TinyExpr is slow compared to C when the
expression is long and involves only basic arithmetic. expression is long and involves only basic arithmetic.
Here is some example performance numbers taken from the included Here is some example performance numbers taken from the included
@@ -212,7 +212,7 @@ Here is some example performance numbers taken from the included
##Grammar ##Grammar
TINYEXPR parses the following grammar: TinyExpr parses the following grammar:
<expr> = <term> {("+" | "-") <term>} <expr> = <term> {("+" | "-") <term>}
<term> = <factor> {("*" | "/" | "%") <factor>} <term> = <factor> {("*" | "/" | "%") <factor>}
@@ -229,7 +229,7 @@ Valid variable names are any combination of the lower case letters *a* through
##Functions supported ##Functions supported
TINYEXPR supports addition (+), subtraction/negation (-), multiplication (\*), TinyExpr supports addition (+), subtraction/negation (-), multiplication (\*),
division (/), exponentiation (^) and modulus (%) with the normal operator division (/), exponentiation (^) and modulus (%) with the normal operator
precedence (the one exception being that exponentiation is evaluated precedence (the one exception being that exponentiation is evaluated
left-to-right). left-to-right).
@@ -246,7 +246,7 @@ In addition, the following C math functions are also supported:
- To allow constant optimization, surround constant expressions in parentheses. - To allow constant optimization, surround constant expressions in parentheses.
For example "x+(1+5)" will evaluate the "(1+5)" expression at compile time and For example "x+(1+5)" will evaluate the "(1+5)" expression at compile time and
compile the entire expression as "x+6", saving a runtime calculation. The compile the entire expression as "x+6", saving a runtime calculation. The
parentheses are important, because TINYEXPR will not change the order of parentheses are important, because TinyExpr will not change the order of
evaluation. If you instead compiled "x+1+5" TINYEXPR will insist that "1" is evaluation. If you instead compiled "x+1+5" TinyExpr will insist that "1" is
added to "x" first, and "5" is added the result second. added to "x" first, and "5" is added the result second.