SCM Builtins: Difference between revisions

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(Created page with "# SCM Builtins ## quote returns a symbol or list without evaluating it **Allowed number of parameters:** 1–1 ### Parameters - **symbol** (`symbol`): symbol to quote ### Returns `symbol` ## eval executes the given scheme program in the current environment **Allowed number of parameters:** 1–1 ### Parameters - **code** (`list`): list with head and optional parameters ### Returns `any` ## size compute the memory size of a value **Allowed number of param...")
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Revision as of 18:16, 25 August 2025

  1. SCM Builtins
    1. quote

returns a symbol or list without evaluating it

    • Allowed number of parameters:** 1–1
      1. Parameters

- **symbol** (`symbol`): symbol to quote

      1. Returns

`symbol`

    1. eval

executes the given scheme program in the current environment

    • Allowed number of parameters:** 1–1
      1. Parameters

- **code** (`list`): list with head and optional parameters

      1. Returns

`any`

    1. size

compute the memory size of a value

    • Allowed number of parameters:** 1–1
      1. Parameters

- **value** (`any`): value to examine

      1. Returns

`int`

    1. optimize

optimize the given scheme program

    • Allowed number of parameters:** 1–1
      1. Parameters

- **code** (`list`): list with head and optional parameters

      1. Returns

`any`

    1. time

measures the time it takes to compute the first argument

    • Allowed number of parameters:** 1–2
      1. Parameters

- **code** (`any`): code to execute - **label** (`string`): label to print in the log or trace

      1. Returns

`any`

    1. if

checks a condition and then conditionally evaluates code branches; there might be multiple condition+true-branch clauses

    • Allowed number of parameters:** 2–1000
      1. Parameters

- **condition...** (`bool`): condition to evaluate - **true-branch...** (`returntype`): code to evaluate if condition is true - **false-branch** (`returntype`): code to evaluate if condition is false

      1. Returns

`returntype`

    1. and

returns true if all conditions evaluate to true

    • Allowed number of parameters:** 1–1000
      1. Parameters

- **condition** (`bool`): condition to evaluate

      1. Returns

`bool`

    1. or

returns true if at least one condition evaluates to true

    • Allowed number of parameters:** 1–1000
      1. Parameters

- **condition** (`any`): condition to evaluate

      1. Returns

`bool`

    1. coalesce

returns the first value that has a non-zero value

    • Allowed number of parameters:** 1–1000
      1. Parameters

- **value** (`returntype`): value to examine

      1. Returns

`returntype`

    1. coalesceNil

returns the first value that has a non-nil value

    • Allowed number of parameters:** 1–1000
      1. Parameters

- **value** (`returntype`): value to examine

      1. Returns

`returntype`

    1. define

defines or sets a variable in the current environment

    • Allowed number of parameters:** 2–2
      1. Parameters

- **variable** (`symbol`): variable to set - **value** (`returntype`): value to set the variable to

      1. Returns

`bool`

    1. set

defines or sets a variable in the current environment

    • Allowed number of parameters:** 2–2
      1. Parameters

- **variable** (`symbol`): variable to set - **value** (`returntype`): value to set the variable to

      1. Returns

`bool`

    1. error

halts the whole execution thread and throws an error message

    • Allowed number of parameters:** 1–1000
      1. Parameters

- **value...** (`any`): value or message to throw

      1. Returns

`string`

    1. try

tries to execute a function and returns its result. In case of a failure, the error is fed to the second function and its result value will be used

    • Allowed number of parameters:** 2–2
      1. Parameters

- **func** (`func`): function with no parameters that will be called - **errorhandler** (`func`): function that takes the error as parameter

      1. Returns

`any`

    1. apply

runs the function with its arguments

    • Allowed number of parameters:** 2–2
      1. Parameters

- **function** (`func`): function to execute - **arguments** (`list`): list of arguments to apply

      1. Returns

`any`

    1. apply_assoc

runs the function with its arguments but arguments is a assoc list

    • Allowed number of parameters:** 2–2
      1. Parameters

- **function** (`func`): function to execute (must be a lambda) - **arguments** (`list`): assoc list of arguments to apply

      1. Returns

`symbol`

    1. symbol

returns a symbol built from that string

    • Allowed number of parameters:** 1–1
      1. Parameters

- **value** (`string`): string value that will be converted into a symbol

      1. Returns

`symbol`

    1. list

returns a list containing the parameters as alements

    • Allowed number of parameters:** 0–10000
      1. Parameters

- **value...** (`any`): value for the list

      1. Returns

`list`

    1. string

converts the given value into string

    • Allowed number of parameters:** 1–1
      1. Parameters

- **value** (`any`): any value

      1. Returns

`string`

    1. match

takes a value evaluates the branch that first matches the given pattern Patterns can be any of: 

- symbol matches any value and stores is into a variable
- "string" (matches only this string)
- number (matches only this value)
- (symbol "something") will only match the symbol 'something'
- '(subpattern subpattern...) matches a list with exactly these subpatterns
- (concat str1 str2 str3) will decompose a string into one of the following patterns: "prefix" variable, variable "postfix", variable "infix" variable
- (cons a b) will reverse the cons function, so it will match the head of the list with a and the rest with b
- (regex "pattern" text var1 var2...) will match the given regex pattern, store the whole string into text and all capture groups into var1, var2...


    • Allowed number of parameters:** 3–10000
      1. Parameters

- **value** (`any`): value to evaluate - **pattern...** (`any`): pattern - **result...** (`returntype`): result value when the pattern matches; this code can use the variables matched in the pattern - **default** (`any`): (optional) value that is returned when no pattern matches

      1. Returns

`any`

    1. lambda

returns a function (func) constructed from the given code

    • Allowed number of parameters:** 2–3
      1. Parameters

- **parameters** (`symbol|list|nil`): if you provide a parameter list, you will have named parameters. If you provide a single symbol, the list of parameters will be provided in that symbol - **code** (`any`): value that is evaluated when the lambda is called. code can use the parameters provided in the declaration as well es the scope above - **numvars** (`number`): number of unnamed variables that can be accessed via (var 0) (var 1) etc.

      1. Returns

`func`

    1. begin

creates a own variable scope, evaluates all sub expressions and returns the result of the last one

    • Allowed number of parameters:** 0–10000
      1. Parameters

- **expression...** (`any`): expressions to evaluate

      1. Returns

`any`

    1. parallel

executes all parameters in parallel and returns nil if they are finished

    • Allowed number of parameters:** 1–10000
      1. Parameters

- **expression...** (`any`): expressions to evaluate in parallel

      1. Returns

`any`

    1. source

annotates the node with filename and line information for better backtraces

    • Allowed number of parameters:** 4–4
      1. Parameters

- **filename** (`string`): Filename of the code - **line** (`number`): Line of the code - **column** (`number`): Column of the code - **code** (`returntype`): code

      1. Returns

`returntype`

    1. scheme

parses a scheme expression into a list

    • Allowed number of parameters:** 1–2
      1. Parameters

- **code** (`string`): Scheme code - **filename** (`string`): optional filename

      1. Returns

`any`

    1. serialize

serializes a piece of code into a (hopefully) reparsable string; you shall be able to send that code over network and reparse with (scheme)

    • Allowed number of parameters:** 1–1
      1. Parameters

- **code** (`list`): Scheme code

      1. Returns

`string`

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