Tempath

Tempath is a template language for path data, which is the superset of SVG Path Data syntax. Inspired by Prototypo's under the hood part.

Usage

Installation

npm install -g tempath

Command line interface

$ tempath --help

Usage: tempath <file> [argument]... [options]

file         path template file
argument     number values that be used to path property

Options:
   -h, --help   print this message

Example

$ echo "prop \$a, \$b, \$c, \$d M 0 0 L \$a+\$b \$c*\$d 6 0 Z" > sample.path

$ cat sample.path
prop $a, $b, $c, $d M 0 0 L $a+$b $c*$d 6 0 Z

$ tempath sample.path 1 2 3 4
M0,0L3,12L6,0Z

Brief Syntax Guide

Since tempath is the superset of SVG path data, you can use all feature of it.

Basic functionalities

M 0,0               # also you can use comment!
L 1,2 3,4           # command letter can be eliminated on same subsequent commands
c 5,6 7,8 9,10      # relative versions of all commands are available

Commands

Tempath code is a list of commands. You can also define your custom command with other commands.

• set: set the variable
• prop: define property that represent the path
• def: define custom command
• if: conditional execution of command
• for: make loop
• import: import foreign template on command

Variable

Variable name starts with $ character.

set $a, 1
set $b, 2
M $a $b     # M1,2

Property

prop command takes a value from outside, and set the value to variable.

prop $a         # Take one value from outside, just set $a by that.

prop $b 0~1     # Take one value from outside,
                # but limit the value into 1~2(inclusive).

prop $c 2       # If there is no value outside, set 2 to $c.

prop $d 3~4 5   # Default value also limited.
                # thus, set 4 when default is used

Expression

Opeator

set $a, 1 + 2 * 3       # set $a to 7
set $b, 1 < 2           # set $b to 1(true)
set $c, 1 = 2           # set $c to 0(false)
set $d, not 1 = 2       # set $d to 1

Builtin Operators

• +
• -
• *
• /
• %
• <
• >
• <=
• >=
• =

Function

Call the function as s-expr style.

set $a, (cos (sin 0))   # set $a to 1

Builtin functions

• ceil
• round
• floor
• sin
• cos
• tan
• sqrt
• atan2

Development

use mocha for generate parser code & test.

$ npm install -g mocha
$ mocha

License

Distributed under MIT License