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parse-float Function

Summary

Parses a float from a string and returns it as float.

Package

hcl

Signature

parse-float string &key start end default-format => float

Arguments
string
A string.
start, end
Bounding index designators for string.
default-format
One of the atomic type specifiers short-float, single-float, double-float, or long-float.
Values
float
A float.
Description

The function parse-float parses a float from the substring of string delimited by start and end and returns it as float.

If the substring represents an integer or the exponent marker is E or is omitted, then float will be of type default-format, which defaults to the value of *read-default-float-format*. Otherwise, its type will match the exponent marker as specified by 2.3.2.2 "Syntax of a Float" in the Common Lisp standard.

If the substring does not represent an integer or a float, then an error of type parse-error is signaled.

Examples
(parse-float "10") => 10.0f0
(parse-float "10" :default-format 'double-float) => 10.0d0
(parse-float "10d0") => 10.0d0
(parse-float "10.5") => 10.5f0
(parse-float "10.5d0") => 10.5d0

LispWorks® User Guide and Reference Manual - 01 Dec 2021 19:30:35